Work/Energy Flashcards
What is Work?
Work is the force acting on an object to cause a displacement
Work must always have…
a displacement
Work Formula
W=Fdcosθ
If the source and displacement are in the same direction…
the work equation can be simplified to
Cosθ=1
The area under a Force vs Displacement graph is
the work done by the force
What is potential energy?
stored energy
What is gravitational potential energy?
energy stored due to an object’s vertical position
Potential energy formula
PE=mgΔh
According to W/E theorem…
Work changes into PE or KE (Together PE and KE make up total mechanical energy)
When there is friction, work can change into
Work can change into internal energy (Heat=Q)
Lifting a box= what change in PE?
an Increase in PE
The work done by hitting a ball on the bat has what impact on the ball?
The work done by hitting a ball on a bat gives the ball KE, causing it to move
Conservation of energy
Energy cannot be created or destroyed
Total energy (ET) of an object or system is constant
Energy can be changed from one form to another
Elastic collision
Collision where energy and momentum are conserved
Change in KE in Elastic collisions?
KE increases as it is going to the ground
0 when it hits the floor
