Newtons Laws Flashcards

Newton's First Law of Motion

An object at rest will remain at rest unless acted on by an outside force. An object in motion will remain in motion unless acted on by an outside force.

Newton's Second Law of Motion

The acceleration produced by a net force is directly proportional to the magnitude of the net force. Ex:F=(m)(a)

Newton's Third Law of Motion

Whenever one body exerts a force on a second body, the second body exerts an equal and opposite force on the first. Ex:Punching a wall or person

Force

A push or pull on an object. A vector quantity. Required to accelerate an object.

Free-Body Diagram

A diagram showing all of the forces acting on an object. All force vectors originate at the center of mass. Ex:a book on a table or pushing a crate

Friction

A constant force that opposes the motion of an object.

Air Resistance

The frictional force air exerts against a moving object.

Pressure

The amount of force per unit of area.

Terminal Velocity

Terminal speed together with the direction of motion.

Action force

The initial push or pull of one object on another.

"m" represents

Mass.

"a" represents

Acceleration.

Equation for acceleration

A = v/t or change in velocity divided by change in time.

What if there is no acceleration?

The velocity will remain constant.

Equation for weight

W = (m)(g) or mass multiplied by gravity.

How is force measured?

In Newtons.

How is pressure measured?

In Pascals or (Pa).

Equation for pressure

P = F/a or force divided by area.

Equation for force

F = (m)(a) or mass multiplied by acceleration.

Doubling the force on an object doubles its

acceleration.

All freely falling objects fall with the same acceleration because

the net force on an object is only its weight, and the ratio of weight to mass is the same for all objects.

The air resistance force an object experiences depends on the object's.

speed and area

The greater the mass…

the greater the terminal velocity.

The more mass an object has…

the more inertia there is.

For a constant force, an increase in the mass will ___________ the acceleration.

decrease

Mass and acceleration are…

inversely proportional.

For a constant force, an increase in the area will result in a ___________ in pressure.

decrease

What causes acceleration?

Force.

What happens if there are unbalanced forces acting on an object?

The object will accelerate.

If the force of sliding friction is 250N, what force is necessary to keep the crate sliding at constant velocity?

250N.

If the mass of a crate is 50kg and sliding friction is 250N, what is the acceleration of the crate when pulling force is 250N, 300N, and 500N?

0m/s^2, 1m/s^2, and 5m/s^2.

What is the net force if an object is at rest?

Zero.

What force would it take to push a 22kg mass at 2m/s^2?

44N.

What is the mass of an object that accelerates at 5m/s^2 from a force of 92N?

95/5kg.

Superman, hearing Lois Lane yell from afar, starts from rest and accelerates to 200m/s^2 in 1.5 seconds, what is his acceleration?

200/1.3m/s^2.

As Superman hears Lois Lane, he drops 68m/s in 4 seconds to get a better view, what is his acceleration?

-17m/s^2.

What is the weight on earth of a girl with a mass of 30kg?

300N

A net force of 15N is exerted on an encyclopedia to cause it to accelerate at a rate of

5m/s^2