36 terms

Mass

The amount of matter in an object; SI unit for measuring mass is the kilogram.

Inertia

A body at motion stays in motion unless acted on by an outside force and a body at rest stays at rest.

Momentum

Mass in motion; a measure of how hard it is to stop the object (p = m*v ---- kg x m/s).

Law of Conservation of Momentum (net momentum before = net momentum after)

In the absence of an external force, the momentum of a system remains unchanged.

Weight

A measure of the force of gravity pulling down on your body; unit for measuring weight is the Newton.

Elastic collision

Two objects bounce off each other.

Inelastic Collision

Two objects sticking to each other.

Friction

Force that opposes motion between two surfaces.

Gravity

Force that pulls all objects together

"closer the objects, the harder the pull"

"greater the mass, larger the pull"; acceleration due to gravity is 9.8 m/s/s on earth (if it weren't for air resistance).

"closer the objects, the harder the pull"

"greater the mass, larger the pull"; acceleration due to gravity is 9.8 m/s/s on earth (if it weren't for air resistance).

Velocity

The speed of the object and the direction of its motion.

To increase impulse

Increase Force and contact time

To calculate momentum

mass x velocity

To calculate impulse

Force x time

To calculate velocity of objects after a collision

net momentum before = net momentum after

Why does the ball have less momentum if you do not follow through?

Decreased contact time

Newton's first law

law of inertia

Newton's second law

acceleration is directly proportional to force and inversely proportional to mass

Newton's third law

action and reaction forces are equal and opposite

Force

A push or a pull

Static friction

Greater force due to the "clinging" of molecules

Sliding friction

Lower force due to the object already being in motion

Free fall

motion of an object with only the force of gravity

Acceleration

Change to an objects motion over an amount of time

vector

includes magnitude and direction

scalar

includes magnitude only

Kinetic energy

energy of an object that is in motion that allows the object to do work

Potential energy

energy of an object due to its position

weight (m x g) x height

gravitational potential energy equation

1/2 m x v ^2

kinetic energy equation

Work

change in energy due to a force being applied to more an object a distance

Thermal energy

due to friction, transformed from KE

Power

work done per an amount of time

F x d

work

W / t

power

Unit of energy and work

Joules

Unit of power

Watts