Pre AP Physics Third Six Weeks Test Chapters 1-5, 6-7 and 10

Multiple Choice

Identify the choice that best completes the statement or answers the question.

1. Human reaction time is usually about 0.20 s. If your lab partner holds a ruler between your finger and thumb and releases it without warning, how far can you expect the ruler to fall before you catch it? (Disregard air resistance.)

a.	at least 4.9 cm	c.	at least 16.0 cm
b.	at least 9.8 cm	d.	at least 19.6 cm

2. Note the figure. Describe the motion of the object graphed at point ‘A’.

a.	The object is passing the origin.	c.	The acceleration of the object is changing.
b.	The velocity of the object is changing.	d.	The acceleration of the object is zero.

3. How do you find displacement from a graph?

a.	The area under the line of a v-t graph.	c.	The slope of a v-t graph.
b.	The area under the line of a p-t graph.	d.	The slope of a p-t graph.

4. Which statement best describes this graph?

a.	An object falling.	c.	An object rising then falling.
b.	An object rising.	d.	An object falling, then rising.

5. What happened when at the time when the object corssed the x axis?

a.	Nothing happened since the slope did not change.	c.	The object stopped moving.
b.	The object turned around.	d.	The object reached the origin.

6. Consider the graph below. What can be calculated from the tangent line?

a.	average velocity	c.	Instantaneous acceleration
b.	average acceleration	d.	Instantaneous velocity

7. Note the two vectors below. Which configuration must these vectors be in so that a vector resolution can be calculated?

a.		c.
b.		d.

8. Note the cannon below. The cannon has a muzzle velocity of 30 m/s. What is the horizontal displacement of the cannonball after one second?

a.	10 m	c.	20 m
b.	15 m	d.	30 m

9. A massive steel ball bearing is thrown straight up into the air. At the top of its trajectory its

a.	velocity and acceleration are 0 m/s and 0 m/s^2.	c.	velocity is 0 m/s and its acceleration is 9.8 m/s².
b.	velocity has increased to its maximum and its acceleration has decreased to its minimum.	d.	velocity has decreased to its minimum and its acceleration has increased to its maximum.

10. Note the cannon illustration below. Study the diagram carefully and note the angle indicated by the three question marks. What is the magnitude of that angle?

a.	10⁰	c.	20⁰
b.	15⁰	d.	30⁰

11. Which graph correctly represents the relationship between force and acceleration?

a.		c.
b.		d.

12. A ball is dropped from a person’s hand and falls to Earth. Identify an action-reaction pair.

a.	The hand exerts a force on the ball; Earth exerts a force on the hand.	c.	Earth exerts a force on the hand; the hand exerts a force on the ball.
b.	Earth exerts a force on the ball; the hand exerts a force on Earth.	d.	Earth exerts a gravitational force on the ball; the ball exerts a gravitational force on Earth.

13. Which of these FBD represents an object in free fall?

a.		c.
b.		d.

14. If a nonzero net force is acting on an object, then the object is definitely

a.	at rest.	c.	being accelerated.
b.	moving with a constant velocity.	d.	moving in a circle.

15. Note the figure. Which vector represents the component of gravity down the incline?

a.	A	c.	Force perpendicular
b.	D	d.	Force parallel

16. What causes a moving object to change direction?

a.	balanced forces	c.	any force
b.	unbalanced forces	d.	horizontal forces

17. According to Newton's first law when an object moves at constant velocity

a.	there is always a small force necessary to keep it going.	c.	all forces acting on it must be balanced.
b.	all forces acting on it must be unbalanced.	d.	there is always a large force necessary to keep it going.

18. Which of the following is the tendency of an object to maintain its state of motion?

a.	force	c.	mass
b.	inertia	d.	weight

19. A 20,000 N car goes forward along a level road at constant velocity. The force required to maintain this constant velocity is equal to

a.	zero.	c.	equal to the weight of the car
b.	the weight of the car divided by its mass.	d.	the force of friction between the car and the road.

20. Which of these FBD represents an object falling at terminal velocity?

a.		c.
b.		d.

21. The equation for power can be written

a.	P = F/v	c.	P = F/t
b.	P = Fv	d.	P = Ft

22. What is the kinetic energy of a 65 kg student running at 3 m/s?

a.	9705 J	c.	292.5 J
b.	195 J	d.	585 J

23. A ball is thrown up into the air. Negating air resistance which statement correctly describes the gravitational potential energy and the kinetic energy of the object?

a.	For half the time both of these energies increase together.	c.	At all times the quantity of these two energies is the same.
b.	For half the time there is no kinetic energy and for the other half there is no gravitational potential energy.	d.	At all times the sum of these two energies is equal.

24. According to the equation for elastic potential energy the energy potential of a spring is a function of

a.	the mass on the spring.	c.	the distance the spring is stretched.
b.	the mass and the distance the spring is stretched.	d.	the square of the magnitude to which the spring is stretched.

25. A kilowatt-hour is actually

a.	3.6 x 10⁶ J	c.	3.6 x 10⁶ J/s
b.	3.6 x 10⁶ Js	d.	3.6 x 10⁶ J s

26. According to the Work-Kinetic Energy Theorem Work is equal to

a.	kinetic energy.	c.	one over kinetic energy.
b.	kinetic energy squared	d.	change in kinetic energy.

27. The kinetic energy of a falling object

a.	always increases.	c.	comes from the mass of the object.
b.	always decreases.	d.	comes from the inertia of the object.

28. Which of these cannot do work on an object?

a.	a perpendicular force	c.	a balanced force
b.	the force of friction	d.	the force of gravity

29. The equation for Impulse is

a.	Ft = Dp	c.	Ft = Fd
b.	Ft = p	d.	Ft = FDd

30. Which of these impulse equations is actually true?

a.	Ft = p	c.	mat = m(v₂-v₁)
b.	mad = mDv	d.	mad = p

31. When an egg traveling at 5 m/s hits a wall it breaks, but when it hits a blanket it does not. This is because when it hit the blanket its

a.	impulse was less than when it hit the wall.	c.	impulse was equal to the impulse when it hit the wall.
b.	impulse is greater than when it hit the wall.	d.	impulse was absorbed by the blanket and not by the wall.

32. The law of conservation of momentum states that the momentum of a system before an event must equal the momentum

a.	after the event .	c.	during the event.
b.	of any of the objects that are part of the event.	d.	of at least half of the objects that are part of the event.

33. Newton knew that an unbalanced force must be acting on the moon because

a.	the moon travels at a constant velocity	c.	the moon is round.
b.	the moon does not travel in a straight line.	d.	only one side of the moon faces Earth.

34. If the force of gravity between two massive objects is 50 N; what will that force be if the distance between them is increased to five times what it was?

a.	2 N	c.	250 N
b.	5 N	d.	1250 N

35. Just as rubber or wood insulate aganist electricity, which, if any of these can insulate aganist gravity?

a.	Water, because it balances gravity with its buoyant force.	c.	Hot air balloons, because they actually fall upwards when properly inflated.
b.	Earth’s atmosphere high above wherein the clouds, containing tons of water, literally ‘float’ on air.	d.	None of these can insulate againist gravity.

36. The equation for calculating Universal Gravitation is

a.		c.
b.		d.

37. How is it that gravity can keep the moon up?

a.	The moon has a large enough tangential velocity.	c.	The moon is outside Earth’s gravitational influence.
b.	Gravity attracts and repels like the electromagnetic force.	d.	The moon is actually imune to the force of gravity.

38. If the force of gravity between two massive objects is 50 N; what will that force be if the distance between them is reduced to one fifth of what it was?

a.	2 N	c.	250 N
b.	5 N	d.	1250 N

39. Which of the following best describes the relationship between two systems in thermal equilibrium?

a.	Their internal energies are equal.	c.	The masses are equal.
b.	Their thermal energies are equal.	d.	No net energy is exchanged.

40. A substance registers a temperature change from 20 °C to 40 °C. This corresponds a change of

a.	-6.66 °F.	c.	36 °F.
b.	11.11 °F.	d.	68 °F.

41. Which of the following is the equivalent of 88°F?

a.	16.9 °C	c.	126.4 °C
b.	31.1 °C	d.	190 °C

42. What temperature has the same numerical value on both the Celsius and the Fahrenheit scales?

a.	– 40°	c.	32°
b.	– 32°	d.	40°

43. Which of the following will keep you warm on a cold winter's night?

a.	A heavy dense quilt	c.	A heavy dense quilt on top of a down comforter
b.	A light down comforter	d.	Several layers of heavy blankets

44. By what means of energy transfer does the sun transfer its energy to the earth?

a.	Conduction	c.	Radiation
b.	Convection	d.	Induction

45. A substance registers a temperature change from 20 °C to 40 °C. This corresponds to a change of

a.	20 K.	c.	36 K.
b.	40 K.	d.	313 K.

46. Which of the following represents a substance in which energy as heat is being absorbed?

a.	gas to liquid	c.	freezing
b.	liquid to solid	d.	boiling

Problem

Solve the problems below and put your answers on the second front of your answerdocument in the section labeled “Griddable D”. Answers should have no more than two decimal places.

47. What is the normal force exerted by a 25⁰ incline on a 500 N box?

48. The coefficient of frction between a 25 N book and a tabel top is 0.34. What force must be applied to this book to move it at a constant velocity across the table?

49. A 60 kg student is gravitationally attracted to his 2000 kg red Honda Accord with a force of 2.0 x 10^-6 N. How far is this student’s center of mass from the Honda’s center of mass? Epxress your answer to two decimal places.

50. How much energy is required to bring 300 g of ice from -5 C to 22 C? Express your answer to two decimal places and let the third decimal place represent the exponent. For example if the answer is 5.248 x 10⁷ you would grid 5.257.