Chap 8. work and power Flashcards
work done=
the amount of energy transferred
what type of energy is stored in your muscle when lifting?
Chemical energy
What 2 factors affect work done?
Size of the force and the distance moved in the direction of the force (further distance, more work done)
What is the equation for work done?
force x distance
what is the conversion from kilonewtons to newtons?
1kN = 1000 N
why is sitting on a chair not doing any work?
Neither forces acting on you are causing any movement. Your energy does not increase or decrease as a result of the forces acting on you.
What is another formula for GPE?
weight x height
weight =
mass x gravity
what unit is (m) in?
kilograms
definition of power:
Power is the rate at which energy is transferred, or the rate work is done at
equation of power (watts W)
work done/time
What does one watt mean?
The power when one joule of work is done per unit time
work done is ALSO equal to:
change in kinetic energy (KE)
how do we calculate average velocity ?
(initial velocity+final velocity)/2
