Download Physics First Semester Exam Review Contrast constant speed

Physics First Semester Exam Review
1. Contrast constant speed, constant velocity, and constant acceleration. ________________________________
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2. What formula is used to calculate average acceleration? ________________________________________________
3. Describe an object’s velocity and acceleration as it falls freely in a vacuum. __________________________
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4. Describe what happens to the speed and distance each second an object falls in free fall. ___________
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5. A ball tossed vertically upward rises, reaches its highest point, and then falls back to its starting
point. During this time the acceleration of the ball is always ____________________________________________.
6. What formula is used to calculate average speed? ________________________________________________________
7. What is the value of the acceleration of an object in free fall? ___________________________________________
8. If a projectile is fired straight up at 30 m/s, how long would it take it to return to its starting point?
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9. Suppose a jumper claims a hang time of 2 seconds. What vertical distance is the jumper able to
jump? ______________________________________________________________
10. After a cannonball is fired into frictionless space, how much force is needed to keep it going?
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11. What would happen to planets if the force of gravity suddenly stopped acting on them?
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12. Why is it that a sheet of paper can be withdrawn from under a container of milk without toppling
it if the paper is jerked quickly? ___________________________________________________________________________
13. If an object has twice as much mass as another object, then the first object also has twice as much
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14. Compared to its weight on Earth, a 10 kg object on the moon will weigh _____________________________.
15. At which of the following locations would you have the largest mass of gold if your chunk of gold
weighed 1 N? the moon, Jupiter, or Earth _________________________________________________________________
16. How do you calculate the weight of an object if you know its mass in kg? ______________________________
17. An object weighs 30 N on Earth and a second object weighs 30 N on the moon. Which has a
greater mass? ______________________________________________________________
18. You and your friend are jumping on a trampoline. Why does Earth, which is rapidly orbiting
around the sun, not move under your feet when you jump? _____________________________________________
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19. A book weighs 4 N. When held at rest in your hands, the net force on the book is ____________________.
20. What equation relates net force, mass, and acceleration? _______________________________________________
21. A box is dragged without acceleration in a straight-line path across a level surface by a force of 13
N. Describe the frictional force between the box and the surface. ______________________________________
22. A tennis ball and a solid steel ball with the same diameter are dropped at the same time. Which
ball has the greater force acting on it? _____________________________________________________________________
23. A block is at rest on an incline. The force of friction necessary to prevent the block from sliding
increases when the incline angle is ________________________________________________________________________
24. A 20 N falling object encounters 4 N of air resistance. What is the net force on the object? __________
25. A student hits a nail with a hammer. During the collision, there is a force on the ____________________.
26. A player catches a ball. Consider the action force to be the impact of the ball against the player’s
glove. What is the reaction to this force? __________________________________________________________________
27. As a ball falls, the action force is the pull of Earth’s mass on the ball. What is the reaction to this
force? _________________________________________________________________________________________________________
28. A bug splatters against the windshield of a moving car. Compared to the force of the car on the
bug, the force of the bug on the car is _____________________________________________________________________.
29. A karate chop delivers a blow of 2300 N to a board that breaks. The force that acts on the hand
during this ____________________________________________________________________________________________________
30. Suppose two people, one having three times the mass of the other, pull on opposite sides of a 20 m
rope while on frictionless ice. After a brief time the meet. The more massive person slides a
distance of ___________________________________.
31. Suppose you accidentally drive into a tree. Describe the interaction between your car and the tree.
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32. If your car runs out of gas, why can’t you push on the car’s windshield from the inside to move it?
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33. At the instant a ball is thrown horizontally with a large force, an identical ball is dropped from the
same height. Which ball hits the ground first? ___________________________________________________________
34. Describe the resultant of a pair of 6-unit vectors at right angles to each other. _______________________
35. Suppose a small plane can fly at 170 km/h relative to the surrounding air. Suppose also that there
is a 60 km/h tailwind. How fast does the plane’s shadow move across the ground? __________________
36. A cannon with a barrel velocity of 140 m/s launches a cannonball horizontally from a tower.
Neglecting air resistance, how far vertically will the cannonball have fallen after 4 s? ________________
37. What is the minimum resultant possible when adding a 5-N force to an 8-N force? ___________________
38. Describe a vector representing the weight of a person. __________________________________________________
39. A 100-N lantern is suspended by a pair of ropes with 120 degrees between them. Describe the
tension in each rope. ________________________________________________________________________________________
40. Suppose you try loosening a nut with a wrench, and the nut doesn’t give at all. How could you
increase your chance of success? ___________________________________________________________________________
41. A meter stick is balanced at the 50.0 cm mark. You tie a 10.0 N weight at the 15.0 mark. Where
should a 30.0 N weight be placed so the meter stick will again be balanced? __________________________
42. A cannonball is launched from the ground at an angle of 30 degrees above the horizontal and a
speed of 30 m/s. With no air resistance the ball will land on the ground with a speed of ____________.
43. A projectile is fired horizontally in a vacuum. Why does it maintain its horizontal component of
speed? ________________________________________________________________________________________________________
44. A cannonball is launched horizontally from a tower. If the cannon has a barrel velocity of 60 m/s,
where will the cannonball be 1 s later? ____________________________________________________________________
45. Describe the potential and kinetic energy of a pendulum swinging back and forth. ___________________
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46. What formula is used to calculate work? __________________________________________________________________
47. A ball is thrown into the air with 100 J of kinetic energy, which is transformed to gravitational
potential energy at the top of its trajectory. Describe its kinetic energy when it returns to its
original level after encountering air resistance. ___________________________________________________________
48. What equation relates kinetic energy, mass, and velocity? _______________________________________________
49. What equation is used to calculate power? ________________________________________________________________
50. What equation is used to calculate momentum? __________________________________________________________
51. What is the purpose of padded dashboards in cars? ______________________________________________________
52. A cannon recoils from launching a cannonball. Why is the speed of the cannon’s recoil small?
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53. A moving freight car runs into an identical car at rest on the track. The cars couple together.
Compare the velocity of the first car before the collision to the velocity of the combined cars after
the collision. __________________________________________________________________________________________________
54. What formula describes the law of conservation of momentum? _______________________________________
55. A truck travels north with a momentum of 2600 kg km/s, and a motorcycle heads west with a
momentum of 1500 kg km/s. The motorcycle hits the truck. If the two vehicles collide and then
stick together, what is the momentum and direction of travel? _________________________________________
56. Compare the period of a satellite in orbit close to Earth to the period of a satellite in orbit far from
Earth. _______________________________________________________________________________________________________
57. Where does a satellite in an elliptical orbit have the greatest kinetic energy? ________________________
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58. What is temperature? ______________________________________________________________________________________
59. What is heat? ________________________________________________________________________________________________
60. The fact that desert sand is very hot in the day and very cold at night is evidence that sand has a
____________________ specific heat capacity.
61. If the specific heat capacity of water were higher than it is, lakes would be ____________________ likely
to freeze.
62. When an iron ring is heated, the hole ____________________________________________________________________.
63. One thousand calories of heat are added to 150 g of water when its temperature is 33 degrees
Celsius. What is the resulting temperature of the water? ______________________________________________
64. Which releases the most energy, 100 g of water cooling 50 degrees Celsius or 100 g of iron cooling
50 degrees Celsius? The specific heat of iron is 0.12 cal/g°C.
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65. Your grandmother places a pitcher of iced tea next to a plate of warm, freshly baked cookies so
that the pitcher and the plate are touching. You tell your grandmother that the plates are in
thermal contact, which means that ________________________________________________________________________.
66. State the first law of thermodynamics. ____________________________________________________________________
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67. State the second law of thermodynamics. _________________________________________________________________
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68. Define entropy. ______________________________________________________________________________________________
69. 80 J of heat are added to a system that performs 55 J of work. The internal energy change of the
system is ____________________________________________________________.
70. What is the formula for Newton’s law of universal gravitation? _________________________________________
71. If you were to weigh yourself in an elevator that is accelerating upward, compared to your
ordinary weight you would weigh _________________________________________________________________________
72. If you were to weigh yourself in an elevator that is in free fall, compared to your ordinary weight,
you would weigh ____________________________________________________________________________________________
73. Why does a piece of metal feel colder than a piece of wood at the same temperature? _______________
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74. If you whirl a tin can on the end of a string and the string suddenly breaks, the can will _____________
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75. An object that has kinetic energy must have ______________________________________________________________.
76. Describe an object at rest in terms of energy, speed, velocity, and momentum. _______________________
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77. A heavy object and a light object are released from rest at the same height and time in a vacuum.
As they fall they have equal ________________________________________________________________________________.
78. Define work. __________________________________________________________________________________________________
79. Describe an elastic collision. ________________________________________________________________________________
80. Suppose a girl is standing on a pond where there is no friction between her feet and the ice. In
order to get off the ice she can ______________________________________________________________________________
81. A meteor that originally was heading south breaks up into two chunks. One of the chunks moves
southwest. The second chunk was not immediately found, but scientists guessed that they should
look for an object heading ____________________________________________________.
82. A large truck and a small car traveling at the same speed have a head-on collision. The vehicle to
undergo the greater change in velocity will be ___________________________________________________________.
83. Two people sit on a balanced seesaw. When one person leans toward the center of the seesaw,
that person’s end of the seesaw will _____________________________________________________________________
84. The fastest moving planet in a solar system is __________________________________________________________
85. An object is placed exactly halfway between Earth and the moon. The object will fall toward
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