Physical Science Chapter 12

The SI unit of force is the

• joule
• kilogram
• meter
• newton

Which of the following relationships is correct?

• 1N = 1 kg

When an unbalanced force acts on an object,

• the object's motion does not change.

• the object accelerates.
• the weight of the object decreases.
• the inertia of the object increases.

When a pair of balanced forces acts on an object, the net force that results is

• greater in size than both forces combined.
• greater in size than one of the forces.
• equal in size to one of the forces.
• equal to zero.

What kind of friction occurs as a fish swims through water?

• fluid
• rolling
• sliding
• static

The forces acting on a falling leaf are

• air resistance and fluid friction.
• gravity and air resistance.
• gravity and static friction.
• weight and rolling friction.

An open parachute increases air resistance of a falling sky diver by

• decreasing the weight of the diver.
• increasing surface area.
• increasing the terminal velocity.
• reducing fluid friction.

Figure 12-1 shows the motion of three balls. The curved paths followed by balls B and C are examples of

• centripetal motion.
• constant motion
• linear motion
• projectile motion

The property of matter that resists changes in motion is called

• friction
• force
• inertia
• weight

An orange might roll off your cafeteria tray when you stop suddenly because of

• the balanced forces acting on the orange.
• the centripetal force acting on the orange
• the friction forces acting on the orange.
• the orange's inertia.