Forces and Motion: Newton’s Laws, Net Force, and Acceleration OLD

What is motion?

The state in which one object's distance from another is changing.

Define frame of reference.

The object or location that you use to describe motion.

What is a unit?

A standard measurement.

What is force?

A push or pull exerted on an object.

Define inertia.

The tendency of an object to resist a change in motion.

What does 'net' refer to in physics?

The sum of all individual forces acting on an object.

What is an independent variable?

The factor or quantity that is changed during an experiment.

Define dependent variable.

A factor or quantity that changes during an experiment because of another factor.

What does Newton's 1st Law state?

An object at rest stays at rest and an object moving at a constant velocity keeps moving unless acted on by an unbalanced force.

How do you calculate net force when forces act in opposite directions?

Subtract the smaller force from the larger force.

How do you calculate net force when forces act in the same direction?

Add the forces together.

What happens to a cart being pulled with equal forces in opposite directions?

The forces are balanced, resulting in a net force of 0N, so the motion remains unchanged.

Why can two observers describe the same train as moving in different directions?

Their frames of reference are different.

Define speed.

The distance an object travels per unit of time.

What is velocity?

Speed in a given direction.

Define acceleration.

The rate at which velocity changes.

What is mass?

The amount of matter in an object.

What does magnitude refer to?

Strength or degree.

What happens to acceleration if mass stays the same and net force increases?

Acceleration will increase.

What occurs if net force stays the same and mass increases?

Acceleration will decrease.

What does Newton's 3rd Law state about action and reaction forces?

They have equal strength and act in opposite directions.

What force does the floor exert on a basketball pushing down with 30N?

The floor pushes up on the basketball with 30N.

Why does the floor not appear to move when a basketball accelerates upward?

The floor has more mass, so it does not accelerate despite the equal force.

Describe the action and reaction forces in a balloon rocket.

Action: the balloon pushes air out; Reaction: the air pushes back on the balloon with an equal force in the opposite direction.