What is the def of force?
That which pushes or pulls through the force of gravity to alter the motion of an object.
Internal and external causes of force?
internal: muscles
external: gravity, other objects, friction
Force equation
force = mass x accel
Must produce a greater what in order to lift something?
must produce a greater force than gravity
A vector has what three things?
magnitude
direction
point of application
a change in magnitude means what?
force applied
a chance in the point of application means what?
where the force is being applied
ex: pushing instead of pulling
Momentum equation
momentum = mass x velocity
newton’s law of reaction
for every action, there is an equal and opposite reaction
what is the def of work?
when force is overcome for a given distance
work equation
work = force x displacement
difference between positive and negative work
positive force: same direction as movement (concentric)
negative force: opposite direction as movement (eccentric)
power definition
the rate at which work is done
power equation
power = work / time
-or-
power = force x displacement / time
-or-
power = force x velocity
velocity equation
displacement / time
-or-
velocity = power / force