1. Definitions: Energy: Work= Force: Ability to do work Force x Distance
A Push or a Pull

2. What is work?
In science, the word work has a different meaning than you may be familiar with.
The scientific definition of work is: using a force to move an object a distance (when both the force and the motion of the object are in the same direction.)

3. Work or Not?
According to the scientific definition, what is work and what is not?
a student carrying a book bag
a mouse pushing a piece of cheese with its nose across the floor

5. What’s work?
A scientist delivers a speech to an audience of his peers. No
A body builder lifts 350 pounds above his head. Yes
A father carries her baby from room to room. No
A mother pushes a baby in a carriage. Yes
A teenager carries a 20 km grocery bag to the car? No

6. What are simple machines?
Simple machines are elementary devices (including levers and pulleys) that provide mechanical advantage.

7. Formula for work Work = Force x Distance The unit of force is newtons
The unit of distance is meters
The unit of work is newton-meters
One newton-meter is equal to one joule
So, the unit of work is a joule

8. Work Equation
Work (joules) = force (newtons) X distance ( meters)
W=Fd
A painter lifts a can of paint that weighs 40 N a distance of 2 m. How much work does she do?

9. TFSA Method T= Title F = Formula S = Substitution A = Answer
What operation are you completing? What are you looking for?
F = Formula
What is the formula used to complete the operation?
S = Substitution
This is where you actually plug in the numbers
A = Answer

10. A painter lifts a can of paint that weighs 40 N a distance of 2 m
A painter lifts a can of paint that weighs 40 N a distance of 2 m. How much work does she do?
T= Title
How much work does she do?
F = Formula
Work = force X distance
S = Substitution
force: f = 40 newtons
distance: d = 2 m
Work = (40n)(2m)

11. A = Anwser
80 (N)(M)
80 Joules
Work = 80 Joules

12. Work Equation
Work (joules) = force (newtons) X distance ( meters)
W=Fd
A painter lifts a can of paint that weighs 40 N a distance of 2 m. How much work does she do?

13. If you push a lawn mower, the horizontal force is 300 N
If you push a lawn mower, the horizontal force is 300 N. If you push the mower a distance of 500 m, how much work do you do?
Title: How much work do you do?
Formula: Work = Force X Distance
Substitute: W =(300n)(500m)
Answer: W = 150,000 newtons meters
W = 150,000 Joules

14. Take a Closer Look at the Six Simple Machines

15. Simple Machines all have one thing in common:
They give their users some form of advantage. They do 3 useful things:
multiply effort
multiply distance
change direction of force

16. Definition:
Mechanical Advantage is a ratio of the load or resistance to the effort or force.

17. Simple Machines Can: Lift and push objects put pressure on objects
hold or break objects
The weight lifted, or the resistance overcome, is the LOAD.

18. Definitions:
Load is the weight or resistance that is moved using a simple machine.
Resistance is an opposing force tending to prevent motion.
Effort is the force applied to move a load using a simple machine.
Force is a push or a pull.
Fulcrum is the point at which a lever arm picots.

20. Water in a hole to deep to reach with a bucket
A boulder too massive to push, role or lift

21. Six Simple Machines
They give their users some form of advantage. They do 3 useful things:
multiply effort
multiply distance
change direction of force

22. LEVER Activity
A lever is a tool that people use to make work easier. Levers are used to lift things or to overcome resistance. Levers give us an advantage by making work easier.
A lever arm is a stick or beam free to pivot at a point.
The fulcrum is the point around which the leve arm pivots.

23. Rules for the Spring Scale
Newtons is the unit used to measure force in the metric system.
1.) Always zero the scales before starting the day’s activity.
2.) Always use the scale right side up, never upside down.
3.) Pull until the lever arm is level, then read the effort. This works best if one student pulls the scale while the another reads the effort.
4.) Stop before the scale goes past the 10-N limit.

24. Inclined Planes
An inclined plane is a flat surface that is higher on one end
Inclined planes make the work of moving things easier
A sloping surface, such as a ramp. An inclined plane can be used to alter the effort and distance involved in doing work, such as lifting loads. The trade-off is that an object must be moved a longer distance than if it was lifted straight up, but less force is needed. You can use this machine to move an object to a lower or higher place.  Inclined planes make the work of moving things easier.  You would need less energy and force to move objects with an inclined plane. 

25. Inclined Plane
The Egyptians used simple machines to build the pyramids. One method was to build a very long incline out of dirt that rose upward to the top of the pyramid very gently. The blocks of stone were placed on large logs (another type of simple machine - the wheel and axle) and pushed slowly up the long, gentle inclined plane to the top of the pyramid.

26. Screw The screw is an inclined plane wound around a central cylinder.
The mechanical advantage of an screw can be calculated by dividing the circumference by the pitch of the screw.
Pitch equals 1/ number of turns per inch.

27. Wedges Two inclined planes joined back to back.
Wedges are used to split things.

28. WHEEL AND AXEL A ferris wheel is an example of a wheel and axle.
Wheel and axel are two different-sized wheels that turn together around the same point.
A ferris wheel is an example of a wheel and axle.

29. Pulleys Pulley are wheels and axles with a groove around the outside
A pulley needs a rope, chain or belt around the groove to make it do work

30. First Class Lever
A Class-1 lever has the fulcrum located somewhere between the effort and the load. E = Effort F = Fulcrum L = Load

31. First Class Lever .
Common examples of first-class levers include crowbars, scissors, pliers, tin snips and seesaws.

32. Second Class Lever
A Class-2 lever has the fulcrum located at one end of a lever arm. The Load is between the fulcrum and the effort has not changed. F = Fulcrum L = Load E = Effort

33. Second Class Lever
Examples of second-class levers include nut crackers, wheel barrows, doors, and bottle openers.

34. F = Fulcrum E = Effort L = Load
Third Class Lever
A Class-3 lever the fulcrum is at one end, and the effort is applied between the fulcrum and the load. The direction of effort is not changed.
F = Fulcrum E = Effort L = Load

35. Third Class Lever
Examples of third-class levers include tweezers, broom, hammers, and shovels.

36. Work and Power – Section 1 – Page 76
If you push a lawn mower, the horizontal force is 300 N. If you push the mower a distance of 500 m, how much work do you do?

37. Work and Power – Section 1 – Page 76
If you push a lawn mower, the horizontal force is 300 N. If you push the mower a distance of 500 m, how much work do you do?
Title: How much work do you do?
Formula: Work = Force X Distance
Substitute: W =(300n)(500m)
Answer: W = 150,000 newtons meters
W = 150,000 Joules

38. Work and Power – Section 1 – Page 77
In the course of a short race, a car does 50,000 Joules of work in 7 seconds. What is the power of the car during the race?

39. Work and Power – Section 1 – Page 77
In the course of a short race, a car does 50,000 Joules of work in 7 seconds. What is the power of the car during the race?
Title: What is the power of the car during the race?
Formula: Power = Work / Seconds
Substitute: P =50,000 J / 7 S
Answer: P = 7, WATT

40. Work and Power –Sec 1 Pg 78
Describe a situation in which work is done on an object.
Evaluate which of the following situation involves more power:
200 J of work done in 20 s or 50 j of work done in 4 s? Explain

41. 200 J of work done in 20 s or 50 J of work done in 4 s?
Title: What is the power?
Formula: Power = Work / Seconds
Substitute: P =200 J / 20 S
Answer: P = 10 WATTs OR
Substitute: P = 50 J / 4 S
Answer: P = 12.5 WATTs

42. Work and Power –Sec 1 Pg 78
3. Determine two ways power can be increased.
Calculate how much power, in watts, is needed to cut a lawn in 50 minutes if the work involved is 100,000 Joules.

43. Calculate how much power, in watts, is needed to cut a lawn in 50 minutes if the work involved is 100,000 Joules.
Title: What is the power needed?
Formula: Power = Work / Seconds
Substitute: P =100,000 J / 3,000 S
Answer: P = WATTs

44. Work and Power –Sec 1 Pg 78 Think Critically:
Suppose you are pulling a wagon with the handle at an angle. How can you make your task easier?