2. Speed and Acceleration Graphs

3. CH10 Question 1 Describe the object’s motion in the graph above.  Move a at constant speed for 4 sec, slows down for 3 seconds then speeds up but not to original velocity.

4. CH10 Question 2 Describe the object’s motion in the graph above.  Move a at constant speed for 4 s, and comes to a rest.

5. CH10 Question 3 Describe the object’s motion in the graph above.  Positive acceleration for 5 seconds – speeds up.

6. CH10 Question 4 Describe the object’s motion in the graph above.  Constant speed 150s, const +accl. For 100 s. Constant speed again for 50 sec, then – accl for one sec.

7. CH10 Question 4 Calculate the object’s acceleration from 150 to 250 seconds.  Vf-Vi/t = 30-10/100= 0,2 m/s 2

8. CH10 Question 4 Calculate the object’s acceleration from 300 to 350 seconds.  Vf-Vi/t = 5 m/s -30 m/s /50 s = -0.5 m/s 2

9. Forces and Motion

10. Question 1 State Newton’s First Law of motion  An object at rest will remain at rest and object in motion remain in motion unless acted on by a net force.

11. Question 2 State Newton’s Second Law of Motion  An object will accelerate in the direction of a net force.

12. Question 3 State Newton’s Third Law of Motion  For every action there is an equal and opposite reaction.

13. Question 1 What is the equation for calculating Force when you know an object’s mass and acceleration?

14. Question 1 What is the equation for calculating Force when you know an object’s mass and acceleration?  Force = mass x acceleration  F = ma.

15. Question 2 What are the units for Force?

16. Question 2 What are the units for Force?  Kg  m/s 2  N = Newton

17. Question 3 A sailboat with a mass of 1000 kg is accelerating at a rate of 8 m/s 2. What is the force of the wind acting on the sail?  F= ma  F = 1000 kg x 8 m/s 2 = 8000 N

18. Question 1 What equation do you use to calculate acceleration if you know the force acting on the object and its mass?  F= ma  A = F/m = F  m

19. Question 2 What are the units for acceleration?  m/s 2  “meters per second squared”

20. Question 3 What is the acceleration of a 50Kg swimmer that pushes off the side of the pool with a force of 100N ?  a = F/m = 100 kg  m/s 2  50 kg = 2 m/s 2

21. Question 1 What is the formula used to calculate mass when you know the Force on an object and the resulting acceleration ?  F = ma  m = F/a = F  a

22. Question 2 A weight lifter accelerates the barbell at a rate of 2.0 m/s 2 with an applied force 400N. What is the mass of the barbell ?  m = F/a = 400 kg m/s 2  5 m/s 2  = 80 kg

23. Question 3 What is the relationship between mass and inertia? ?  As the mass increases the inertia of an object increases and a greater force will be required to accelerate the object.

24. Question 1 What is the formula used to calculate the weight of an object on Earth?  weight = mass x gravitational acceleration.  Gravitational acceleration on earth = 9.8 m/s 2

25. Question 2 What is the difference between mass and weight?  Mass is a measure of how much matter an object contains.  Weight is a measure of the force of gravity acting on that mass.

26. Question 3 Calculate the weight of 10 kg of gold sitting on your desk.  weight = mass x a g  a g =9.8 m/s 2  W = 10 kg x 9.8 m/s 2 = 98 N

27. Question 1 Name this equation and the variables that compose it.

28. Question 1 Name this equation and the variables that compose it.  Universal Gravitation  F = force of gravity  G = gravitational constant  m = mass of the objects  D 2 = distance between the objects

29. Question 2 According to the equation what happens to the gravitational force between two objects when they get farther apart?

30. Question 2 According to the equation what happens to the gravitational force between two objects when they get farther apart? d 2 increases and the force of gravity gets smaller.

31. Question 3 According to the equation why does our sun have a gravitational force strong enough to hold all the planets in orbit even though some are very far away.

32. Question 3 According to the equation why does our sun have a gravitational force strong enough to hold all the planets in orbit even though some are very far away.  The sun has a very large mass so its gravitational force is large and far reaching.

33. Question 1 What is the term used to describe an object where the only force acting on the object is gravity ?  Free Fall

34. Question 2 This is the maximum velocity a falling object will reach as the upward force of air resistance equals the downward force of gravity ?  Terminal velocity

35. Question 3 If an object at terminal velocity is experiencing balanced forces, how can the object still be falling ?  Balanced forces only mean that the object is not ACCELERATING, it still falls @ a constant velocity.

36. Question 1 A fluid includes which three states of matter?  Liquids, gases, and plasmas

37. Question 2 What is the formula used to calculate pressure and what unit is pressure reported in?  P = mass  Area = N/m 2 = Pa  Usually kPa (kilo Pascals)

38. Question 3 What is the air pressure if 20 N is exerted over an area of 10m 2 ?  P = mass/Area = 20N  10m 2  = 2 Pa

39. Question 1 According to Bernoulli’s Principal what happens to the pressure of a fluid as the velocity of the fluid increases?

40. Question 1 According to Bernoulli’s Principal what happens to the pressure of a fluid as the velocity of the fluid increases?  The pressure decreases.

41. Question 2 What is the upward force exerted on an object immersed in a fluid?  Buoyant force or buoyancy.

42. Question 3 Archimedes Principal states that for an object to float the weight of the object must be equal to or less than.... ?

43. Question 3 Archimedes Principal states that for an object to float the weight of the object must be equal to or less than.... ?  the weight of the fluid displaced by the object.

44. Question 1 What term is used to describe the resistance of of a gas or liquid to flow?  Viscosity.

45. Question 2 Hydraulic devices can increase the output force by increasing the output area. Which principal predicts this characteristic?  Pascal’s Principal- the pressure of a liquid in an enclosed system is uniform throughout the system.

46. Question 3 According to the Venturi effect, what happens to the velocity of a fluid when it is forced to flow through a smaller area??  The velocity of the fluid increases..

47. Question 1 What is the term for any object thrown or launched from Earth under the influence of gravity?  Projectile

48. Question 2 Describe the horizontal and vertical forces acting on the cannon ball.

49. Question 3 Which will hit the ground first, the cannon ball dropped straight down or the one launched sideways? They both hit at the same time – horizontal motion is independent of vertical free-fall.