Mrs inertia

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					Mrs. Umbarger                                                        Name
Physics                                                              Date
Semester 2 Final                                                     Per.

Chap. 10
True or False

____ 1. The point located at the geometric center of an object is called the object’s
center of gravity.

____ 2. When an object is balanced so that a displacement raises its COG , the object is
said to be in neutral equilibrium.

____ 3. When an object is balanced so that a displacement neither raises nor lowers it
COG, the object is said to be in unstable equilibrium.

____ 4. By standing with your feet apart on a bumpy bus ride, you increase your
stability by allowing you to use your muscles for support.

____ 5. Because the sun has several planets orbiting it, it actually wobbles as it move
through space.

Multiple Choice

_____ 6. The long heavy tail of a spider monkey enables the monkey to easily vary its
             a. weight                            b. momentum
             c. inertia                           d. center of gravity

_____ 7. An object will fall over if its CG is
             a. too high                      b. too low
             c. outside the object            d. not over its area of support

_____ 8. An object thrown into the air rotates about its
             a. midpoint                    b. edge
             c. geometric center            d. center of gravity

_____ 9. Based on stability concepts, you would expect a very broad tree to have
             a. a very broad root system
             b. very deep roots
             c. exceptionally strong roots

_____ 10. In which of the following is the COG located at a point where there is no
mass?        a. Glass of milk               b. Cookie
             c. Pineapple                   d. Donut
Chapter 11
True or False

_____ 11. The distance between a turning axis and the point of contact of a
perpendicular force is called the fulcrum.

_____ 12. Torque is the product of a force exerted on an object times the lever arm.

_____ 13. In order for a seesaw to be in rotational equilibrium, the sum of the torques
acting on it need not be balanced.

_____ 14. Gymnasts change their rotational inertia while doing their gymnastic routines.

_____ 15. A spinning wheel will maintain its state of angular momentum unless acted
on by an external torque.

Multiple Choice

_____ 16. Angular momentum is defined as
            a. rotational inertia x linear velocity b. mass x velocity
            c. momentum x rotational velocity d. none of the above

_____ 17. Suppose you try loosening a nut with a wrench and the nut doesn’t move.
You increase your chance of success if you
              a. extend the lever arm         b. exert force perpendicular to lever arm
              c. exert a larger force         d. all of the above

_____ 18. The resistance an object has to changes in its rotational state of motion is
called rotational    a. momentum                   b. inertia
                     c. torque                     d. acceleration

_____ 19. Angular momentum is defined as
            a. mass times velocity
            b. rotational inertia times linear velocity
            c. momentum times rotational velocity
            d. none of the above

_____ 20. A meter stick is balanced at the 50 cm mark. You tie a 20 N weight at the 30
cm mark. Where should a 30 N weight be placed to maintain its balanced?
            a. 20 cm                              b. 30 cm
            c. 50 cm                              d. 70 cm

Chapter 12
True or False
_____ 21. The component of an orbiting satellite’s velocity that is parallel to Earth’s
surface is its tangential velocity.

_____ 22. There is a force on Earth that is directed toward the sun.

_____ 23. Because Earth is “falling” around the sun, it will eventually crash into it.

_____ 24. The force on a ball decreases as the ball moves farther from Earth.

_____ 25. If the Earth were its present size but twice as massive, we would weigh less.

Multiple Choice

_____ 26. Newton hypothesized that the moon
            a. is a projectile                       b. is actually attracted to Earth
            c. is falling around Earth               d. all of the above

_____ 27. If Earth’s mass decreased to ½ its original mass, with no change in radius,
then your weight would
              a. decrease by ¼                     b. decrease by ½
              c. stay the same                     d. none of the above

_____ 28. Gravitational forces are the weakest forces found in nature. Because of this
            a. gravitational effect between a pencil and the earth cannot be seen
            b. there is no gravitational force between two 1-kg masses
            c. gravitational effects occur only when a large mass is involved
            d. none of the above

_____ 29. Suppose the gravitational force between two massive spheres is 10-N. If the
distance between the spheres is cut in half, what is the force between the masses?
              a. 40 N                                  b. 20 N
              c. 10 N                                  d. 5 N

_____ 30. A supplier wants to make a profit by buying metal by weight at one altitude
and selling it at the same price per pound at another altitude. The supplier should
                 a. buy at a high altitude and sell at a low altitude
                 b. buy at a low altitude and sell at a high altitude
                 c. disregard altitude because it has no effect on weight

Chapter 13
True or False

_____ 31. When the properties of space are altered in such a way that a mass in that
space experiences a force, the space is said to contain a gravitational field.

_____ 32. When Earth’s shadow falls on the moon, a lunar eclipse occurs.
_____ 33. When the moon’s shadow falls on Earth, a solar eclipse occurs.

_____ 34. If Earth had its present mass but twice the radius, the acceleration due to
gravity would increase.

_____ 35. Because Earth has mass, it also has a gravitational field.

Multiple Choice

_____ 36. The value of acceleration due to gravity
            a. depends on the radius of Earth      b. depends on the mass of Earth
            c. is different on different planets d. all of the above

_____ 37. The gravitational field strength at the center of Earth is
            a. large                                 b. the same as on the surface
            c. smaller than on the surface           d. zero

_____ 38. If you were to weigh yourself in an elevator that is accelerating upward,
compared to your ordinary weight you would weigh
              a. more                              b. less
              c. the same                          d. zero

_____ 39. A black hole is an object that
             a. has an enormous density                b.has an enormous gravitational field
             c. alters space around it                 d. all of the above

_____ 40. According to Newton’s laws, a rock and a pebble will fall with the same
acceleration in a gravitational field because the gravitational force on each is
       a. the same
       b. different, though the ratio of the force to the mass of each is the same
       c. none of the above

Chapter 14
True or False

_____ 41. The time for a satellite to completely orbit the Earth is its frequency.

_____ 42. The place in a satellite’s orbit where the satellite is closest to the Earth is the

_____ 43. The sum of a satellite’s kinetic energy and potential energy varies as the
satellite orbits a planet.

_____ 44. The speed of a satellite in a circular orbit changes as it circles the Earth.
_____ 45. An Earth satellite is a projectile that falls around the Earth instead of falling
into it.

Multiple Choice
_____ 46. Where does a satellite in an elliptical orbit have the greatest kinetic energy?
             a. at the point farthest from the planet
             b. at the point closet to the planet
             c. exactly at the point halfway to the planet

_____ 47. Where does a satellite in an elliptical orbit have the greatest potential energy?
            a. at the point farthest from the planet
            b. at the point closet to the planet
            c. exactly at the point halfway to the planet

_____ 48. The curvature of the earth is such that for every 8000 m tangent to the
surface, the surface drops about
                a. 20 m                             b. 10 m
                c. 5 m                              d. 2.5 m

_____ 49. The force of gravity does work on a satellite when it is in
            a. circular orbit                     b. elliptical orbit
            c. both A and B                       d. neither A and B

_____ 50. The fastest moving planet in a solar system is
            a. the smallest planet                 b. the most massive planet
            c. an planet nearest the sun           d. they all move the same speed

Chapter 15, 16
True or False

_____ 51. Time is relative.

_____ 52. Motion is relative.

_____ 53. The speed of light is relative.

_____ 54. The speed of a train driving past a car is relative.

_____ 55. Mass and energy are equivalent.

Multiple Choice

_____ 56. A change in energy of any object at rest is accompanied by a change in
             a. speed                              b. mass
             c. volume                             d. all of the above
_____ 57. If an object has a lot of momentum, it
              a. moves fast                          b. is massive
              c. greatly resists change              d. all of the above

_____ 58. Space contracts
            a. in the line of motion                 b. perpendicular to line of motion
            c. in all directions                     d. space doesn’t contract

_____ 59. The universe’s speed limit is
            a. infinite                              b. equal to escape speed
            c. the speed of light                    d. incalculable

_____ 60. In YOUR opinion a scientist should be
             a. responsible for the outcome of their discoveries
             b. making scientific discoveries for science’s sake
             c. limited based on society’s moral values

Chapter 17
True or False

_____ 61. Electrons, protons, and neutrons combine to form atoms, which can be
considered the building blocks of all matter.

_____ 62. Atoms and molecules are in a state of constant agitation known as Brownian

_____ 63. A compound is a substance made from atoms of different elements that are
combined in a fixed proportion.

_____ 64. Atoms are nearly empty space. However, at the center of an atom is a mass-
filled region called the nucleus.

_____ 65. A nucleus contains particles that are generally classified as electrons.

Multiple Choice

_____ 66. Elements that are side by side in the periodic table have one more or one less
             a. proton                       b. nucleon
             c. electron shell               d. ion

_____ 67. Elements that are above or below each other in the periodic table have one
more or one less    a. proton                    b. nucleon
                    c. electron shell            d. ion

_____ 68. Most of the matter in the universe is in which phase?
            a. liquid       b. solid       c. gas                   d. plasma
_____ 69. Keep heating a gas and you will have a
            a. liquid      b. plasma      c. both A and B           d. neither A and B

_____ 70. How many electrons can the innermost shell of an atom have?
            a. 8          b. 6           c. 4                  d. 2

Chapter 18
True or False

_____ 71. The elastic limit of an object is surpassed when the object doesn’t return to its
original shape after being stretched.

_____ 72. Scaling is the study of how size affects the relationship between weight,
strength, and surface area.

_____ 73. Because cells obtain nourishment through their surfaces, there is an upper
limit on the size of a living cell.

_____ 74. Rock samples are made of regular geometric shapes called crystals.

_____ 75. The stretch of a spring is inversely proportional to the applied force.

Multiple Choice

_____ 76. A 10-kg load stretches an elastic belt 0.02 m. How much will a 15-kg load
stretch the belt?
                a. 0.05 m          b. 0.04 m              c. 0.03 m

_____ 77. A metal block has a density of 5000 kg per cubic meter and a volume of 2
cubic meters. What is the block’s mass?
              a. 1000 kg            b. 5000 kg           c. 10 000 kg

_____ 78. Which cooks faster in boiling oil?
            a. a whole potato      b. a sliced potato       c. both cook equally fast

_____ 79. A block of iron is heated in a furnace, where it consequently expands. In the
expanded condition, its density is
             a. less                b. the same             c. more

_____ 80. When a solid block of material is cut in half, its density is
            a. halved             b. unchanged               c. doubled

Chapter 19
True or False
_____ 81. An object will sink in water if its density is greater than the density of water.

_____ 82. The weight of fluid displaced by a floating object is equal to the weight of the

_____ 83. Pressure in a fluid is inversely proportional to the depth at which the pressure
measurement is taken.

_____ 84. The buoyant force on a submerged rock depends on the volume of the rock.

_____ 85. Because concrete’s more dense than water, a ship made of concrete will sink.

Multiple Choice

_____ 86. Archimedes’ principle says that an object is buoyed by a force that is equal to
the         a. weight of the fluid displaced      b. volume of the fluid displaced
            c. mass of the fluid displaced        d. mass of the object

_____ 87. An egg is placed at the bottom of a bowl filled with water. Salt is slowly
added to the water until the egg rises and floats. From this one can conclude that
              a. the density of salt water exceeds the density of egg
              b. buoyant forces do not always act upward
              c. salt sinks to the bottom

_____ 88. The reason an iron ship doesn’t sink is that
            a. iron is less dense than water        b. air inside decreases it’s weight
            c. the iron displaces more water than it would if it were in a solid block

_____ 89. Pascal’s principle says that changes in pressure at any point in an enclosed
fluid        a. are transmitted to all points in the fluid
             b. quickly diminish from point to point in the fluid
             c. remain only at the point

_____ 90. In a hydraulic device, the output piston has 100 times the cross-section area
as the input piston. This means the device will multiply force
                a. 10 times          b. 100 times           c. 1000 times

Chapter 20
True or False

_____ 91. A fluid can be either a gas or a liquid.

_____ 92. A barometer is an instrument used for measuring water pressure.

_____ 93. Boyle’s law expresses a relationship between pressure and temperature of a
_____ 94. Suppose gas molecules inside a box are held at the same temperature. As the
volume of the box increases, the pressure increases also.

_____ 95. Bernoulli’s principle states that pressure in a fluid decreases as the speed of
the fluid decreases.

Multiple Choice

_____ 96. The main difference between gases and liquids is that in a gas
            a. molecules are moving faster
            b. forces between molecules are larger
            c. distances between molecules are larger

_____ 97. Most hand pumps used in wells rely on
            a. sucking action                   b. atmospheric pressure
            c. Boyle’s law                      d. Archimedes’ principle

_____ 98. If you squeeze a balloon to ½ its original size, the pressure inside
              a. increases by 4                     b. increases by 2
              c. stays the same                     d. decreases by 2

_____ 99. Consider an air-filled balloon, weighted with a stone that just barely floats in
water. When the balloon is pushed beneath 1-m below the surface and released, it will
             a. float back to the surface b. stay where it is     c. sink

_____ 100. As a high-altitude balloon sinks lower and lower into the atmosphere, its
            a. volume decreases            b. density decreases c. weight decreases

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