Ch. 3 - Forces and Newton's Laws

Front

What are the ways to reduce friction?

Back

1. Reduce the force acting between the two surfaces. 2. Reduce the roughness of the surfaces in contact. 3. Use wax, grease, or oil. 4. All of the above.

Front

Who is credited with the law of universal gravitation?

Back

Newton.

Front

What is the definition of net force?

Back

The overall force acting on an object when all the individual forces are combined.

Front

What is an example of harmful friction?

Back

Engine parts wearing out.

Front

What is the net force if two equal forces of 20 N act in opposite directions?

Back

0 N.

Front

What is friction?

Back

A force that opposes the motion of an object.

Front

What is Newton's First Law of Motion?

Back

An object at rest stays at rest, and an object in motion stays in motion unless acted upon by a net external force.

Front

What is Newton's Second Law of Motion?

Back

The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass (F=ma).

Front

What is Newton's Third Law of Motion?

Back

For every action, there is an equal and opposite reaction.

Front

What is the formula for calculating net force?

Back

Net Force = Total Forces acting in one direction - Total Forces acting in the opposite direction.