Physics WPE Flashcards
Conservative Force
Dosen’t interfere with energy of a system
Non conservative force
Takes away or adds to the energy of a system
What are the only two conservative forces
Gravity and Spring
Unit for work
Joules
Unit for power
Watts
Who does more work when climbing stairs?
Everyone does the same amount of work if the stairs are the same height
Who has more power when climbing up stairs?
The person with more mass and in less time
If a force increases KE, it does______ work
Positive
If a force decreases KE, it does ______ work
Negative
Work formula
Force x displacement
Work energy theorem
PE + KE + W = PEf + KEf
PE formula
Mass x height x gravity
KE formula
1/2 x mass x Velocity squared
Is work scalar or vector
Scalar
Is power scalar or vector
Scalar
Is energy scalar or vector
Scalar
Scalar
Only magnitude not direction
Vector
Magnitude and direction
Formula for power
Work divided by time
As an object goes up it’s PE ______
Increases
As an object goes down it’s KE _____
Increases
On the ground PE is always
0
For staircase problems, if the object moves off the top, how do you find its PEf
Add the number of Joules to the total PE
What happens if an object speeds up
It loses PE and gains KE
