Force

According to Newton's first law of motion, an object at rest will remain at rest and an object in motion will continue moving in a straight line at constant speed unless acted upon by a ________.

• gravity

• velocity

• force

• friction

Which of Newton's laws states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass?

• Newton's third law of motion

• Newton's second law of motion

• Newton's law of universal gravitation

• Newton's first law of motion

Friction is a force that opposes the motion of objects that are in ________ contact with each other.

• indirect

• perpendicular

• direct

• parallel

Which type of friction occurs when an object moves through a fluid, such as air or water?

• Rolling friction

• Static friction

• Surface friction

• Fluid friction

Gravity is the force of attraction between two objects with ________.

• density

• mass

• weight

• volume

What is the formula to calculate momentum?

• p = ma

• p = mv^2

• p = m^2v

• p = mv

Which of the following is an example of circular motion?

• A boat sailing in a straight line

• A person walking in a straight line

• A car moving around a circular track

• A plane flying in a straight line

What is the centripetal force?

• The centripetal force is the force that pulls an object away from its circular path.

• The centripetal force is the force that causes an object to slow down in a circular path.

• The centripetal force is the force that pushes an object towards the center of a circular path.

• The centripetal force is the force that keeps an object moving in a circular path.

Which of Newton's laws explains why a person in a moving car tends to keep moving forward when the car suddenly stops?

• Newton's first law of motion

• Newton's law of universal gravitation

• Newton's third law of motion

• Newton's second law of motion

Which force opposes the motion of an object sliding down a hill?

• momentum

• gravity

• inertia

• friction