1. Task: Find out . . . What is a force? What is force measured in?
What is Sir Isaac Newton famous for?
Explain your answer to question two in more detail.
What is friction?
Give an example of when friction would be useful?
Give an example of when friction would be unwanted ?

2. Starter
Lesson 1
Take a new page in your jotter and create a cover page with the title “Forces” in large letters. As you complete the topic, when you finish a task early, you can add new pictures and words to your cover page.

3. FORCES

4. Forces “Rocket Science”
This topic is called Forces and it is a physics topic.
Other scientific terms you can use to describe this Forces topic include:
“Dynamics”
and
“Rocket Science”
The first few slides are a simple introduction to Forces, and concentrate mainly on forces in space. (This usually easily captures the imagination of the young people).

5. Science CfE Experiences & Outcomes
I have collaborated in investigations to compare magnetic, electrostatic and gravitational forces and have explored their practical applications. [SCN 2-08a ]
By investigating floating and sinking of objects in water, I can apply my understanding of buoyancy to solve a practical challenge. [SCN 2-08b]
By contributing to investigations of energy loss due to friction, I can suggest ways of improving the efficiency of moving systems. [SCN 3-07a]
I have collaborated in investigations into the effects of gravity on objects and I can predict what might happen to their weight in different situations on Earth and in space. [SCN 3-08a]
By making accurate measurements of speed and acceleration, I can relate the motion of an object to the forces acting on it and apply this knowledge to transport safety [SCN 4-07b]
I can help to design and carry out investigations into the strength of magnets and electromagnets. From investigations, I can compare the properties, uses and commercial applications of electromagnets and supermagnets. [SCN 4-08a]

6. The picture on the first slide was of Space Shuttle Atlantis taking off from Florida, USA on a journey to the International Space Station.
A massive amount of force is required to lift the shuttle off the Earth’s surface and accelerate it towards space.
Do any pupils in the class have any experience of this? Have seen this on tv? What does it look like and sound like?

7. Video Clip – Space Shuttle Launch
The next slide will show a video clip of the Space Shuttle Atlantis taking off from Earth, on its way to the International Space Station.
There is a HUGE amount of force involved here.
Are you sure you want to turn the volume right up for this!!! (The video clip should play automatically.)

9. International Space Station
The International Space Station (ISS) is a science laboratory in space (220 miles above Earth- a low Earth orbit).
It orbits the Earth 8 times a day.
The force of gravity on the ISS is small.
We call it microgravity. (There is actually no such thing as zero gravity.)
Do you know any more facts???
Pupils should have some STEM background to talk about facts they know!

10. Video Clips – ISS
This short video clip will let you take a look at what it is like on board the ISS:
Video Clip - Inside the ISS 2min 34s
This video clip will let you observe an astronaut drinking coffee on the ISS:
Video Clip - Drinking Coffee inside the ISS 2min 42s

11. Think! How old is the universe?
In a study published  in the journal Science, a team of researchers say the universe is between 11.2 billion and 14 billion years old.

12. Forces Learning Intentions:
An introduction to Forces and what they do.
Success Criteria:
Be able to state three things that forces can do.
Be able to represent a force using arrows in simple situations.
Be able to state the unit we use to measure force.

13. All forces can change the speed of an object shape of an object
What forces can do
All forces can change the
speed of an object
shape of an object
or the direction of an object.
Watch this video clip
Roberto Carlos Super Goal
0min 13s
Check out these two clips and observe the effects of forces:
smart car crash 5min 40s
stopping distance 1min 32s

14. Tiger Woods – golf ball changing speed, shape and direction

15. Forces
An arrow can be used to represent a force.
The size of the arrow tells us how big the force is.
The direction of the arrow tells us the direction of the force.
The objects can be stationary or moving.

16. Activity: Using arrows to show forces.
On the smart board show the size and direction of any or all the forces that are acting.
The larger the arrow, the larger the force.
Use Activ Inspire to annotate over the pitcures

17. Weightlifting Bar

18. Gymnast on Rings

19. Curling Stone

20. Diver on Springboard

21. Rowing Boat

22. Archery Arrow

23. Tug-Of War Rope

24. Sumo Wrestler

25. Gymnast on Beam

26. We can measure forces using a Newton balance.
Units of Force
Force is measured in units called newtons, N. For example the thrust force of this rocket is 200 newtons or 200 N, in an upwards direction.
We can measure forces using a Newton balance.
200 N

27. Were you successful? Learning Intentions:
An introduction to Forces and what they do.
Success Criteria:
Be able to state three things that forces can do.
Be able to represent a force using arrows in simple situations.
Be able to state the unit we use to measure force.

28. Lesson 2 - Starter Does a light year measure speed, distance or time?
A light year measures distance.
What is a light year?
The distance that light travels in a vacuum in 1 year : 5.88 trillion miles or 9.46 trillion kilometres

29. Measuring Force Learning Intentions:
Use a Newton balance to measure force.
Success Criteria:
Be able to name common types of contact forces and the situations in which they occur (friction, upthrust, tension and supporting forces).
Be able to name different types of non-contact forces and the situations in which they occur (electric force, magnetic force, force of gravity).

30. Using a Newton balance or Forcemeter
Force is measured in Newtons (N).
A forcemeter/Newton balance is an instrument used to measure forces.

31. Some things to check before using a Newton balance
When there is nothing attached to the hook the balance should read zero. If not adjust the screw at the top of the balance.
Always check that you are reading off from the Newtons (N) scale not the grams (g) scale.
Choose the right balance for the right job. Some balances have springs in them that are thin and won’t take much force others are thick and will be able to take much larger forces. So when you apply the force and the reading on the balance is off the scale then choose a stronger balance.

32. Newton balance activity
Copy the following table.
Choose the correct newton balance then measure the force used in each of the actions.
Choose the last two actions yourself and find the force!
Action
Force (N)
Open the class door
Lift your pencil case
Lift your school bag
Open a cupboard door
Your choice
You should now be able to do Homework 2

33. Contact Forces
Contact forces occur between objects that are touching. Sometimes we think of forces as simple pushing, pulling, twisting or supporting forces. Some obvious examples of contact forces in action are
Pushing a pram or shopping trolley
The dog pulling its owner
Turning (twisting) a door handle
A bridge supporting a truck
If you think about it we are surrounded by forces all the time. Some of these are useful and work for us and some not so useful and work against us.

34. All forces can cause pushes, pulls and twisting effects on an object.
Some contact forces have special names and we will examine some of these in closer detail in the lessons in this topic.
Some of these are:
Friction when surfaces rub together;
Upthrust (buoyancy) in fluids-(boats and hot air balloons;
Lift force in air (planes and birds);
Tension in ropes and cables; and
Surface tension on the surface of liquids.

35. Contact Forces Friction when surfaces rub together;
Upthrust (buoyancy) in fluids-(boats and hot air balloons;
Lift force in air (planes and birds);
Tension in ropes and cables; and
Surface tension on the surface of liquids.

36. Forces that can act over a distance
electrical force
magnetic force
force of gravity (weight)

37. Forces that can act over a distance
Some forces can act over a distance without touching.
Click on each link for a demonstration
electrical force
Electrical Force Video Clip 0 min 35 seconds
magnetic force
Magnetic Force Video Clip 0 min 18 seconds
force of gravity (weight)
Force of Gravity Video Clip 1 min 10 seconds

38. Contact forces Non-contact forces supporting force twisting
Which force is which?
Contact forces
Non-contact forces
supporting force
twisting
magnetic force
electrical
tension
surface tension
friction
upthrust
Forces that act over a distance without touching or Non-contact forces are the Electrical force, Gravity and the Magnetic force.
gravity(weight)
lift

39. Were you successful? Learning Intentions:
Use a Newton balance to measure force.
Success Criteria:
Be able to name common types of contact forces and the situations in which they occur (friction, upthrust, tension and supporting forces).
Be able to name different types of non-contact forces and the situations in which they occur (electric force, magnetic force, force of gravity).

40. Lesson 3 - Starter What is a black hole?
A black hole is a region of spacetime from which nothing can escape, even light.
How far is the nearest black hole?
As of now the closest known one is thought to lie at about 1,600 light years from Earth.

41. Friction Learning Outcomes: Discuss the force of friction.
Success Criteria:
Be able to state that friction is a force which tries to stop an object moving or slow it down.
Be able to give examples of this.

42. Friction
When two surfaces rub together a force called friction will act to slow the movement down and convert the kinetic energy to heat energy .
For example, a cyclist is slowed down by the air moving over them: not a good thing. However, for a falling parachutist the air friction reduces their speed so they can land safely, which is very useful.
The friction forces produced when we rub our hands together converts the kinetic energy into heat energy, which is a good thing on a cold day. Try it now! However, for the moving parts in a car engine, the large amounts of friction causes a lot of the kinetic energy to be wasted as heat.
Can the pupils think of any other examples.

43. Activity: Separate the two books joined only with friction.
Collect two paperback books and “interweave” the pages as shown.
Try to separate the books by pulling in the direction of the arrows.
The force of friction holds the two books together.

44. Friction video
Some questions for you to think about while watching the clip:
In which situations can friction occur?
When can friction be a useful thing?
When can friction become a problem?
(22 mins)
Time permitting teacher could demonstrate the linear air track, balloon/cd hover pucks, oiled hinges and brick on wooden rollers to show ways of reducing friction.

45. Friction
Friction occurs when two surfaces are in contact with each other.
Friction is a contact force.
Friction is a force that will oppose movement.
Friction will slow down a moving object.

46. Some other video clips about friction:
Overcoming friction (2min30)
Friction on the Ski Slopes (2min30)
Friction between the Tyre and the Road (1min20)
Testing Friction (3min)

47. Were you successful? Learning Outcomes: Discuss the force of friction.
Success Criteria:
Be able to state that friction is a force which tries to stop an object moving or slow it down.
Be able to give examples of this.

48. Lesson 4 - Starter What is a supernova?
A supernova is a stellar explosion which produces an extremely bright object made of plasma that declines to invisibility over weeks or months. 

49. Streamlining Learning Intentions: Discuss streamlined objects.
Success Criteria:
Be able to recognise situations in which friction occurs and factors that increase or decrease friction (air friction, streamlining, lubrication).
Be able to contribute to class discussions about streamlined objects.

50. Video clip: Porsche v VW Beetle
The link below will show a video clip of a Porsche racing a VW Beetle.
Porsche v VW Beetle 4 min 40s
At the end of the video clip, discuss with your teacher and classmates any situations you spotted that:
have a high degree of friction
Are designed to reduce friction (streamlining)

51. Reducing the effects of friction: Streamlining

52. What do all these things have in common?

53. Activity: Rocket Science
Working in groups of two you are going to make two “rockets”.
One that is streamlined and one that is less streamlined and observe the effect of the difference in streamlining on the distance travelled when the rockets are fired.

54. Rocket Launcher Safety Guidelines
A proper risk assessment done in context is the responsibility of the teacher using the apparatus.
Over pressurising the system does not appear to be a hazard as all that happens is that the joints part. However resealing the joints after this has happened can be tricky and time consuming. Hence we would recommend that 60 psi is a safe maximum pressure to use and the projectiles will have a decent maximum range.
It would be sensible to have a firing procedure. For example, everyone behind a given line, check tube is facing away from people and rocket is in place, pump launcher up, check that it’s clear to fire, fire after countdown.
It has been known for the white plastic launch tube to move when a rocket is fired. Tightening the plastic elbow joint should stop this or failing that resting a bean bag or something of similar weight on the tube ought to stop this.
Avoid having ears near the end of the open tube when testing the launcher. The air coming out could be quite forceful.
Don’t fire the projectiles at people or near sensitive areas. Paper rockets falling from the sky onto unsuspecting cars would not be desirable and military bases may not be amused.

55. Rocket building You will need: 35 cm of plastic pipe
2 sheets of A4 card
sticky tape
a penny
Scissors
Trundle wheel
Rocket launching apparatus
Safety goggles

56. roll one sheet of A4 card “length-wise” around the piece of plastic tubing
place a piece of sticky tape along the join to make a cylindrical shape.

57. put tape all along the edge of the roll of card
the tube needs to be airtight!

58. Tape over one end of the tube then tape a penny over taped end of the tube and secure it with a few strips of tape.

59. Nose cone and tail fins On the other card draw and cut out
two semicircles of diameter 16cm
4 tail fins that are narrow
4 tail fins that are broad

60. Rocket Nose Cone
Roll and shape one of the semi circles into a “narrow” cone shape and tape the join securely.
Place nose cone over “penny” end of the tube and secure to the tube with plenty of tape.
Form the other semi-circle into a “broad” cone shape and leave to one side.

61. Rocket Tail Fins
Attach the four tail fins to the base and a team name to complete the rocket as shown.
You are now ready to fire your rocket.
Sharples

62. Your teacher will take you outside to a suitable location in the playground and you can fire your rocket using the launcher.
Make sure you take with you the broad nose cone and tail fins, and some sellotape and scissors.
Once your first rocket is fired make a note of where it lands.
Bring the rocket back to the launching area and replace the nose cone and tail fins with the broader versions and fire the rocket again.
Compare how far it travels with the broader cone and fins compared to the more streamlined version.

63. Reducing friction
Streamlining an object will reduce the amount of friction. For example; the smooth, curved surfaces of an aircraft.
Lubricating surfaces in contact with each other will reduce the friction. For example; oil on a bike chain.
You should now be able to do Homework 3

64. Lesson 5 - Starter
Complete the build of rocket!

65. Rocket Science Learning Intentions: Compare streamlined objects
Success Criteria:
Be able to discuss the effect that streamlining your rocket had on the distance it travelled.

66. Copy and Complete Write a conclusion based on these results. Group
Normal Distance (m)
Streamlined Distance (m) 1 2 3 4 5 6 7 8 9 10
Write a conclusion based on these results.

67. Were you successful? Learning Intentions: Compare streamlined objects
Success Criteria:
Be able to discuss the effect that streamlining your rocket had on the distance it travelled.

68. Lesson 6 - Starter What is the big red spot on Jupiter?
The Great Red Spot on Jupiter is a hurricane-like storm system. It is large enough that two Earths could fit across it. 

69. Gravity Learning Intentions:
Learn about force and how it gives an object weight.
The difference between mass and weight.
Success Criteria:
Be able to describe gravity and it’s effect on an object.
Be able to state that mass is the amount of matter in a body measured in kilograms.
Be able to describe how mass doesn't change but weight changes depending on the force of gravity.
Be able to explain that on Earth the weight is 10 x the mass. Weight = 10 x mass

70. What do these two have in common?
This is Sir Isaac Newton
This is an apple, much similar to the one that fell on Newton’s head that led him to discover gravity!

71. Gravity is the force that keeps our feet on the ground – literally!
A famous Italian scientist and philosopher called Galileo did some interesting experiments on the leaning tower of Pisa to prove how gravity works.
This experiment was later recreated on the moon!
Galileo Experiment 4min

72. More about Gravity
This is the force that pulls objects towards the Earth.
On Earth, objects fall at different rates because air resistance pushes up on objects at the same time.
On Earth, the cannon ball falls to the ground first. This feather falls last. This is because the feather has to work harder against air resistance.
WHAT HAPPENS IF THERE IS NO AIR RESISTANCE?
On the moon, there is no air resistance, so nothing will push up against the feather or cannonball. The force of gravity is the same for both objects so they will fall at the same time.

73. Video Clip – Dropping a hammer and a feather on the Moon
An astronaut repeated Gallileo’s famous experiment on the Moon by dropping a hammer and a feather at the same time.
Which one do you think will reach the surface of the Moon first?

74. Activity. The connection between Mass and Weight
In this activity you will find out the connection between mass and weight.
Collect a red newton balance and a stack of ten slotted masses on their hook.
Slide off all the masses until there is just the hook with one disc.
Holding the newton balance vertically measure the weight in Newtons for the hook with one 100g disc.
Slide another disc on and so on recording the new weight each time a disc is added.
Record your results on the table on the next slide.

75. Measuring Weight and Mass Complete the table below:
Mass (kg)
Weight (N)
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
You may wish to try a different object. Use the scales to complete the mass (kg).

76. Weight and Mass
Mass is the amount of matter in an object and is measured in kilograms (kg).
Weight is the force of gravity acting on an object and is measured in Newton’s (N).
1 kilogram of mass has a weight of 10 Newton’s on Earth.
Weight = mass x 10 or mass = weight ÷ 10

77. State the units of weight. The units of weight are
Mass and Weight
What is mass?
Mass is the amount of
State the units of mass.
are the units of mass
What is weight?
Weight is the force of
State the units of weight.
The units of weight are
How are mass and weight related on Earth?
Mass = or weight =
What is the weight of a boy, who has a mass of 35kg?
What is the mass of a girl, who has a weight of 325N?
You should now be able to do Homework 4

78. Lesson 7 - Starter
What is the most common element found in the universe?
Hydrogen
What is a red giant?
They are stars of times the mass of the Sun which have exhausted their supply of hydrogen in their cores and switched to fusing hydrogen in a shell outside the core.

79. Buoyancy Learning Intentions: Learn about upthrust (buoyancy force).
Success Criteria:
Be able to explain that an object apparently weighs less in water because water produces upthrust (buoyancy force).
Be able to carry out investigations which demonstrate effects of density on floating/sinking.

80. Buoyancy Force
Around the room you will find 4 activities to illustrate the buoyancy force. At each activity there is an information sheet explaining the activity to you. In your notes jotter write the name of each activity and describe what you discovered.
Activity sheets can be found in Folder named Buoyancy. These sheets should be laminated and come as part of the resources pack from the lab technicans.

81. The activities are:
Eyedropper Diver
Float an Egg
Dancing Raisins
What Floats your Boat

82. More on Buoyancy Youtube video on Why things float 3min 34s
How submarines work animation (scroll down half a page and click on the submerge button)

83. How submarines work
A submarine can submerge by taking on board more water into its tanks. This makes it heavier and it sinks.
The submarine can surface by then pumping out the water from these tanks replacing the water with air. This makes it lighter and therefore it floats to the surface.

84. NASA Neutral Buoyancy Lab Houston, Texas

85. NBL Characteristics
The NBL was sized to perform two activities simultaneously; each uses mock-ups sufficiently large to produce meaningful training content and duration. It is 202 ft in length, 102 ft in width, and 40 ft in depth (20 ft above ground level and 20 ft below) and holds 6.2 million gallons of water. Even at this size, the International Space Station, at 350 ft x 240 ft when complete, will not fit inside the NBL.

86. What is Neutral Buoyancy?
Neutral buoyancy is the term used to describe something that has an equal tendency to float as it does sink.
Neutral buoyancy is currently the best available method for astronauts to train for EVA (space-walking).
EVA stands for extra vehicular activity.

87. Were you successful? Learning Intentions:
Learn about upthrust (buoyancy force).
Success Criteria:
Be able to explain that an object apparently weighs less in water because water produces upthrust (buoyancy force).
Be able to carry out investigations which demonstrate effects of density on floating/sinking.

88. Lesson 8 - Starter What is a friggatriskaidekaphobiac afraid of?
Answer: fear of Friday the 13th

89. Object’s Weight Learning Intentions:
The effect of the environment on an objects weight.
Success Criteria:
Be able to explain the change in apparent weight when an object is in different situations on Earth (water, air) and in space.

90. Floating and Sinking Complete the following table Block material
Weight in air (Newtons)
Weight in water (Newtons)
Change in weight (Newtons)
Rubber
Plastic
Wood
Foam

91. Method
Collect a drip tray, large plastic beaker of water, newton balance, a rubber band and a cube.
Drop the cube into the water to see if it floats or sinks. Then double wrap the rubber band tightly around the cube and hook it onto the newton balance.
Hold the balance vertically and accurately record the weight in Newton’s in the table. Push your finger under the object. What happens to the reading on the Newton balance?
Then lower the cube into the water in the plastic beaker and accurately record the new weight.
Work out any difference in the weight.
Repeat this with the other four blocks and complete the table.
Click on this link to see an animation showing upthrust reduces the weight of a rock

92. Buoyancy Force
Buoyancy force (or upthrust) is a force that acts upwards on an object when it is in a liquid (ship) or a gas (helium balloon).
If the buoyancy force is greater than or equal to the weight of the object it will float.
If the buoyancy force is less than the weight of the object it will sink.
You should now be able to do Homework 5

93. Were you successful? Learning Intentions:
The effect of the environment on an objects weight.
Success Criteria:
Be able to explain the change in apparent weight when an object is in different situations on Earth (water, air) and in space.

94. Lesson 9 – Starter 1
What is Jupiter made of and how many moons does it have?
Jupiter is about 90% hydrogen and 10% helium (by numbers of atoms, 75/25% by mass) with traces of methane, water, ammonia and "rock“.
Jupiter has 63 known satellites (as of Feb 2004): the four large Galilean moons plus many more small ones some of which have not yet been named.

95. Learning Outcomes Forces at a distance
State that electrical forces can act at a distance between electrically charged objects only and can attract or repel.
State an application of the electrical force (paintsprayer)

96. Success Criteria
Be able to collaborate in investigations to compare magnetic, electrostatic and gravitational forces and explore their practical applications.

97. What is the name of this device?
You may wish to allow pupils to participate in the experiment.

98. Static Electricity Video Clips
- 3mins 40 sec mins 12 sec

99. Electrostatic Force
Method:
Collect an inflated balloon and an empty aluminium can.
Place the can on its side on the bench.
Rub the balloon on your hair and place close to but not
touching the can.
Observations:
What happened to your hair?
What happened to the can?
Will the balloon stick to your body?

100. Electrostatic Force
Now cut up a 10cm piece of a plastic bag and make it into a shape like a comb.
This time rub the balloon and the piece of plastic at the same time.
Now place the plastic on top of the balloon.
What happens?

101. Electrostatic Force Video
Electrostatic Levitation
2min 46s

102. Application of the electrostatic force Video
(1min 40)

104. An application of the electrical force

105. Starter – Copy and Complete Electrical force
Electrical forces can act at a distance between electrically charged objects.
Two negative charges _____________________ each other.
Two positive charges ______________________ each other.
A positive charge and a negative ___________________ each other.

106. Home research task
Find another application of the electrostatic force and present it to the class.

107. Lesson 10 – Starter Inside your car.
Where is the safest place to be in a thunderstorm?
Inside your car.
When electricity passes through a metal box into the Earth it only tracks over the surface and does not pass through the interior.

108. Learning intentions: State that magnetic forces act at a distance
Learning intentions: State that magnetic forces act at a distance. State that magnetic forces are produced by permanent magnets and electromagnets. State which metals are attracted to a magnet.

109. Experiment 1 Collect a magnet, and a jar of mixed filings
Experiment 1 Collect a magnet, and a jar of mixed filings. Put the magnet onto the glass and move it around. What do you notice?

110. Experiment 2
Collect a magnet.
Test various objects in the room.
Record your finding.

111. The magnetic force can act over a distance.
There are only three elements attracted to a magnet .
These are _____________, ______________ and cobalt.
Steel is also attracted to a magnet because it ___________ _______.
Cobalt, nickel and iron are the three naturally magnetic elements. Steel contains iron.

112. Making an Electromagnet: Experiment
Collect
A “C” shaped iron core
A long piece of wire
A Westminster low voltage electrical supply
Two crocodile
clips
Two leads
Paper clips
Warning:
Must use the Westminster low voltage supply only!
Keep croc clips and bare wires apart! Switch off after a few seconds!
Wind the wire around the core leaving a
few cm of wire at each end.
Attach croc clips to the bare metal ends
of the wire.
Connect the leads from the red and black
outputs on the supply to the croc clips.
Try to see if you can pick up any of the paper clips.
Try again using the yellow outputs on the supply.
Write down a description of how to turn a piece of iron into an electromagnet using a labelled diagram.
Do not USE LOW VOLTAGE WESTMINSTER POWER PACKS OR LOCKABLE VOLTAGE POWER SUPPLIES SET AT 4 VOLTS MAX. Don’t leave the electromagnets on for too long to avoid over heating. Avoid bare wires and croc clips touching to avoid sparking. See technician

113. Making an electromagnet
Wind a length of wire around a piece of iron and pass electricity through the wire using a battery. The more turns of wire and the more electric current there is then the stronger the electromagnet.
Iron nail + -
Battery
wire

114. Strong Electromagnets
Making an Electromagnet
2 min 43s
Would you be able to suspend a toy car using your electromagnet?

115. Application of the magnetic force
This is a simple electric motor.
The teacher could show the pupils a working model or allow them to build a model one.
Your teacher will now show you a working model of a simple motor.
115

116. Application of Supermagnets
The strongest permanent magnet is a neodymium magnet.
What happens if these are dropped down a metal tube?
Some practical applications;
Computer hard drives
Magnetic Resonance Imaging
These magnets are dangerous . Be very careful when using them. They can catch your skin between them.
116

117. Magnetic Resonance Imaging Video (7 min)

118. Lesson 11 - Starter How long is a day on Mercury?
Mercury rotates three times in two of its years.
Mercury has very, very long days.
Each day on Mercury lasts as long as 58 days, 15 hours on Earth. This is quite a feat, considering a whole year on Mercury is only 88 days.

119. What we will do today:
Recognise that if an object is stationary or is travelling at a constant speed then the forces are said to be balanced.
Recognise that if the forces acting are not equal and opposite in direction, they are said to be unbalanced and the object accelerates.

120. Balanced and unbalanced forces
If two forces are acting on an object in opposite directions, the object will move in the direction of the larger force.
If the two forces are the same size but in opposite directions, they balance out. These forces are called balanced forces.

121. Balanced and unbalanced forces
Click on the following link and follow carefully the on screen prompts. (Click on the grey arrow head prompt before clicking on the green next button.)
Balanced and Unbalanced Forces
1min 24s

122. 16 Newtons
50 Newtons
30 Newtons
25 Newtons
Unbalanced Forces
300 Newtons
100 Newtons

123. Balanced Forces

124. Animation showing balanced forces

125. Balanced and unbalanced forces
Copy and complete.
When the forces acting on an object are equal and opposite, they are called ___________ ______.
If the forces are balanced, the object will stay still or carry on at the same __________ in the same direction.
You should now draw examples of balanced and unbalanced forces in your jotter.

126. Lesson 12 - Starter What is a constellation?
A constellation is a group of stars that, when seen from Earth, form a pattern. 
How many named constellations are there?
There are 88 constellations. 

127. What we will do today:
State that reducing the forces in a car crash is important in reducing the harm to the people involved. This can be done by decreasing speed and using devices/materials to help absorb the impact forces.

128. Challenge: Build and design a crash barrier/car bumper
Your challenge is to construct an impact absorbing device that will reduce the force experienced by the toy car or trolley.
Using recycled materials – card, paper, sponge, bubble-wrap and tape etc you have to construct a device that is no more than 3cm deep.
Test your car on the test track and measure the force accurately without a crash barrier and then with your device. Find the difference in the two forces.
The team with the biggest reduction in force wins the challenge.
Note – there is a Word Document on the car crash barrier investigation available in “additional” folder.

129. Write -up
Briefly describe your crash barrier investigation using simple diagrams and a short paragraph stating your aim, method, results and a conclusion.

130. Collisions
If we reduce the forces we experience during a collision we can reduce the amount of damage to our body.
This can be done by:
Driving at the correct, safe speed;
Using good engineering design in our cars and roadside objects; and
using appropriate materials in these designs to absorb impact forces.

131. Lesson 13 - Starter Video clip as lesson starter
So you think you're the centre of the Universe. Think again!!!
2min 34s
The lesson starter is aimed at provoking discussion on planets, solar systems, Galaxy etc

132. Forces in Space What we will do today:
Explain that gravity is a far reaching force that acts to hold satellites and moons in orbit around planets, hold planets in orbit around a star (solar systems) and hold large collections of stars in a galaxy (Milky way).

133. Even more about the force of Gravity
View the following clip about the gravitational influence of the Sun
Gravity is a force that exists between objects that have mass.
The larger a planet’s mass the more gravity it has.
It is a force that can reach out over extremely long distances.

134. How stuff stays in orbit
When you throw an object horizontally it follows a curved path before it hits the ground. If the object is thrown horizontally with sufficient sideways speed it will stay in orbit, provided nothing is in it’s path.
Check out the animation below. It’s a reworking of Newton’s cannon, an idea that Sir Isaac Newton came up with as to how an object may remain in orbit around the Earth. If you click on the “fire” button a cannon ball will fire from the cannon. You can click “next” and try varying the speed to see if you can launch the cannonball into orbit.

135. Forces in space
All objects are pulled to the Earth by __________________.
If a satellite has enough sideways speed it can stay in _____________, even though it is falling towards the earth all the time. This happens because the Earth’s curved surface is curving away from the satellite at the same rate that it is falling towards Earth and so never hits the Earth.
The _________________ is a natural satellite of the Earth.
The long reaching force of gravity holds the Earth and the other planets in orbit around the ______________________.

136. Distance from Sun (millions km) Time to orbit sun (years)
The Solar System
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Pluto
Diameter (km)
5000
12000
12800
7000
140000
120000
52000
50000
3000
Distance from Sun (millions km) 60
110
150
250
780
1400
2900
4500
6000
Time to orbit sun (years)
0.2
0.6 1 2 12 30 84
160
Gravity 4 9 10 26 11 5

137. Use the table on the previous slide to help you answer these questions.
Write these objects in order of size starting with the smallest:
planet, star, moon
How long does it take the Earth to orbit the Sun?
(a) which is the biggest planet?
(b) Is the biggest planet as large as the Sun?
Which planet has large rings?
Which planet come between the Earth and Jupiter
Which planet is nearest the Sun
Which planet is furthest from the Sun?
Which planet do you think will be the coldest?
Which planet is almost the same diameter as the Earth?
Which planets are larger than Earth?
Which planet moves round the Sun in:
The shortest time
The longest time
What pattern can you see between the distance from the Sun and the time taken for 1 orbit?

138. Answers
Moon, planet, star
One year.
(a) Jupiter
(b) No
Saturn
Mars
Mercury
Pluto
Venus
Jupiter and Saturn
a) Mercury b) Pluto
The closer a planet is to the sun, the shorter the time taken for it to orbit the sun. Or the further away a planet is from the sun, the longer the time taken for it to orbit the sun.

139. Graphs
Draw a bar graph of the diameters of the planets – the information is in the table on one of the previous slides.
For the first four planets, plot a line graph of the time taken to travel one orbit around the Sun against the distance from the Sun.
The asteroids are large rocks that travel around the Sun at an average distance of 400 million km. Use your graph to estimate how long they take to make one orbit of the Sun.

142. The Solar System Song

143. Space race and sputnik video clip 3min20s

144. Hubble Space telescope news clip 1min15s

145. Prof Brian Cox clip about Hubble 1min25s

146. BBC fact files on all the moons

147. An odd fact about gravity
Although gravity is a force able to hold in orbit massive, planet sized objects millions and millions of kilometres apart it can be considered to be quite a weak force. We know this because when we lift any every day object or jump up in the air we regularly overcome this force with the minimum of effort. This is something that scientists don’t quite fully understand yet.

148. Lesson 14 - Starter http://www.youtube.com/watch?v=HEheh1BH34Q
Sizes of Planets and Stars
2 min 34 s

149. What we will do today:
State that a black hole is an object with such a high gravitational field that even light is not fast enough to escape from it.

151. Black holes
A black hole is a region of space from which nothing, not even light, can escape. Black holes have such a large mass that they produce a huge gravitational force. This force is so large that even light is not travelling fast enough to escape it and therefore they are called black holes.
(start from 4min)

152. Black holes and escape velocity
To escape the gravitational pull of the earth your spaceship would need to travel at metres every second.
To escape from the surface of the Sun and overcome it’s gravitational pull you would need to be travelling at m/s.
To escape from the smallest black hole your spaceship would need to be travelling at a speed greater than m/s which sadly is not possible, according to present Physics theory.

153. Black holes
Black holes have such a strong gravitational pull it is thought that there is a black hole Watch this video: “How we can see a black hole”
at the centre of each galaxy that has a strong enough gravitational force to hold all the billions upon billions of stars that make up the galaxy.
If you were pulled into a black hole you would be “spaghettified”: literally stretched out into a long thin piece of “human spaghetti”.

154. Watch this video: “How we can see a black hole”

155. The following slide is an artists impression of a binary star system in the constellation of the Swan Cygnus. At the centre of Cygnus X-1 there is thought to be a Black Hole. On the left is a bright blue supergiant star designated HDE , which is estimated as having about 30 times the mass of our Sun. Cygnus X-1 is depicted on the right, connected to its supergiant companion by a stream of gas, and surrounded by an impressive accretion disk. The massive gravitational force from the black hole at the centre of Cygnus X-1 is stripping a stream of gas from its neighbouring star.