Forces and Motion Test

When air resistance exactly matches the downward force of gravity, a falling object stops accelerating and reaches ______________________.

• terminal velocity
• momentum
• mass
• inertia
• air resistance

An object at rest tends to remain at rest. This property is called ______________________.

• inertia
• momentum
• mass
• air resistance
• centripetal force

Only in a vacuum or in space can an object be in ______________________.

• free fall
• momentum
• mass
• inertia
• air resistance

A car accelerating from 60 km/h to a constant speed of 80 km/h has increased its ______________________.

• momentum
• air resistance
• mass
• inertia
• centripetal force

The horizontal movement given to an arrow by a bow is one component of ______________________.

• projectile motion
• momentum
• mass
• inertia
• air resistance

If three balls of steel, rubber, and plastic were dropped at the same time from the same height, which would hit the ground first? (Assume there is no air resistance.)

• a. All would hit at the same time.
• b. The rubber ball would hit first.
• c. The steel ball would hit first.
• d. The plastic ball would hit first.

A spacecraft orbiting Earth is both moving forward and

• a. at terminal velocity.
• b. in free fall.
• c. experiencing resistance.
• d. weightless.

Assuming 1 kg = 1,000 g, a 5 kg object has less inertia than an object with a mass of

• a. 4 kg.
• b. 6,000 g.
• c. 2 kg.
• d. 1,500 g.

Newton’s first law of motion states that a moving object, unless it is acted on by an unbalanced force, will

• a. remain in motion.
• b. eventually come to a stop.
• c. change its momentum.
• d. accelerate.

An astronaut uses a jet of nitrogen to maneuver in space. This can be done because of

• a. orbiting.
• b. free fall.
• c. momentum conservation.
• d. inertia.