Chapter 2: Forces and Motion

Gravity

Friction

Inertia

Air resistance

Force is the product of mass and inertia.

A moving object will speed up unless a force acts on it.

A moving object will slow down unless a force acts on it.

An object does not change its state of motion unless a force acts on it.

Greasing the wheel of the wheelbarrow

Moving the wheelbarrow onto a paved sidewalk

Adding a pile of dirt to the wheelbarrow

Holding the handles of the wheelbarrow with gloves

Electricity

Air resistance

Gravity

Magnetism

A decrease in mass

An increase in force

A decrease in force

All of the other answer choices

Only Team A will start to move.

Only Team B will start to move.

Both teams will start moving.

Both teams will remain in the same place.

it has inertia.

friction does not affect it.

it has increasing acceleration.

gravity pulls it forward.

An elevator speeding up

An elevator slowing down

A car driving at constant speed

A car driving around a curve at constant speed

There are no forces acting on the lawnmower.

The only force acting on the lawnmower is gravity.

Tom is applying a force on the lawnmower.

The total force on the lawnmower is zero.