Chapter 6 Forces

What happens when two forces act in the same direction?

• They cancel each other out.

• The stronger one prevails.

• Their strengths are added

• Their sum divided by two is the total force.

The greater the mass of an object,

• the easier the object starts moving.

• the greater its inertia.

• the more balanced it is.

• the more space it takes up.

The force of gravity on a person or object on the surface of a planet is called

• mass

• terminal velocity

• weight

• free fall

The force that one surface exerts on another when the two rub against each other is called

• friction

• acceleration

• inertia

• gravity

The law of universal gravitation states that any two objects in the universe that have mass, without exception,

• attract each other

• repel each other

• combine to provide a balanced force

• create friction

Forces can be added together only if they are

• acting on the same object

• balanced forces

• unaffected by gravity

• substantial

According to the law of conservation of momentum, when two objects collide in the absence of outside forces,

• velocity decreases

• velocity increases

• the objects have the same momentum before and after they collide

• the objects have more momentum after they collide than they did before

Any force that causes an object to move in a circle is called a(n)

• balanced force

• unbalanced force

• gravitational force

• centripetal force

The momentum of an object is in the same direction as its

• force

• acceleration

• velocity

• inertia

According to Newton’s third law of motion, when a hammer strikes and exerts force on a nail, the nail

• creates a friction with the hammer

• disappears into the wood

• exerts an equal and opposite force on the hammer

• moves at a constant speed