Physics Final ~ Inertia

T/F An astronaut weighs the same on Earth as in space

F

T/F If a hockey puck slides on a perfectly frictionless surface it will eventually slow down because of its inertia

F

T/F If you were to slide a hockey puck across a friction less ice rink, there must be a horizontal force on it to keep it in motion

F

T/F Inertia is the property that ever material object has; inertia resists changes in an object's state of motion.

F

T/F The SI unit force is called the kilogram

F

T/F The SI unit of force is the kilogram

F

T/F The SI unit of mass is the newton

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T/F The amount of matter in an object is called its weight.

F

T/F The amount of matter in an object is its weight

F

T/F The force due to gravity acting on it is its mass

F

How much (in newtons) does 0.60 kg of salami weigh?

6 N

A person weighs 650 N. What is the mass of the person?

65 kg

How much (in newtons) does a 10.0-kg bag of grass seed weigh?

100 N

On the surface of Jupiter, the acceleration due to gravity is about 3 times that on Earth. How much would a 0.40 kg rock weigh on Jupiter?

12 N

On the surface of Jupiter the acceleration due to gravity is about 3 times that on Earth. How much would a 100 kg rock weigh on Jupiter?

300 kg

T/F A force can be simply defined as a push or pull

T

T/F An astronaut has the same mass on Earth as in space

T

T/F Friction refers to the force between two surfaces that are sliding past each other

T

T/F Inertia is the reluctance any material object has to change in its state of motion

T

T/F The combination of all the forces that act on an object is called the net force

T

T/F The reason a penny thrown straight up inside an airplane will come back to your hand is that you, the air inside the plane, and the penny are all moving at the same horizontal velocity

T

Compared to its mass on Earth, the mass of a 10-kg object on the Moon is a) the same b) more c) less

a

Compared to its weight on Earth, a 10-kg object on the Moon is a) the same amount b) less c) more

b

Friction is a force that always acts a) perpendicular to an object's motion b) opposite to an object's motion c) in the same direction as an object's motion

b

Galileo found that a ball rolling down one inclined plane would roll how far up another inclined plane. a) to nearly twice the height as where it originally started b) to nearly the same height as where it originally started c) to nearly half its original height d) to about one quarter its original height

b

You and a friend are jumping on a trampoline. Why does Earth, which is rapidly orbiting around the Sun, not move under your feet when you jump? a) There are different rules in space and on the surface of Earth b) Newton's first law holds that your body moves along with Earth because with Earth because its not compelled to change its motion by an unbalanced force c) Newton's second law holds that the acceleration produced by the force of gravity is offset by the force of friction on your feet d) Newton's third law holds that there is an equal and opposite force exerted by the trampoline on your feet, which allows you to move with Earth through space

b

A 10-N force and a 30-N force act on an object in opposite directions. What is the net force on the object? a) 40 N b) 30 N c) 20 N d) 10 N

c

A sheet of paper can be withdrawn from under a container of milk without toppling if the paper is jerked quickly. The reason that this can be done is that a) gravity pulls down very hard on the milk b) the milk carton has very little weight c) the milk carton has inertia d) none of the above

c

An object following a s straight-line path at constant speed a) has no forces acting on it b) has a net force acting on it in the direction of motion c) has zero acceleration d) must be moving in a vacuum e) none of the above

c

If the force of gravity suddenly stopped acting on the planets, they would a) spiral slowly towards the Sun b) continue to orbit the Sun c) move in straight lines tangent to their objects d) spiral slowly away from the Sun e) fly straight away from the Sun

c

One object has twice as much mass as another object. The first object also has twice as much a) velocity b) gravitational acceleration c) inertia d) all of the above

c

The law of inertia applies to a) moving objects b) objects at rest c) both moving an non moving objects

c

Which has more mass, a kilogram of feathers or a kilogram of iron a) the feathers b) the iron c) Neither. The masses are equal.

c

Which has more mass, a kilogram of feathers or a kilogram of iron? a) the feathers b) the iron c) Neither-they both have the same mass

c

Whirl a rock at the end of a string and it follows a circular path. If the string breaks the tendency of the rock is to a) follow a circular path b) continue to follow a circular path c) follow a straight-line path

c

After a cannon ball is fired into a friction less space, the amount of force needed to keep it going equals a) twice the force which it was fired b) the same amount of force which it was fired c) one half the force which it was fired d) zero, since no force is necessary to keep it moving

d

Friction a) comes from microscopic bumps that act as obstructions to the object's motion b) is the name given to the force acting between surfaces sliding past one another c) acts in directions that opposes the motion of an object d) all of the above e) none of the above

d

How much does a 3.0 kg bag of bolts weigh? a) 7.2 N b) 14.4 N c) 22.8 N d) 29.4 N e) 58.8 N

d

The law of inertia states that an object a) at rest will remain at rest unless acted by an outside force. b) will continue moving at the same velocity unless an outside force acts on it c) will continue moving in a straight line unless an outside force acts on it d) all of the above

d

On the surface of Jupiter, the acceleration due to gravity is about 3 times that on Earth. What would be the mass of a 170 kg rock on Jupiter?

the mass would be the same