Physics P1 Flashcards
What are the 7 energy stores?
Kinetic, gravitational potential, elastic potential, thermal, chemical, nuclear and magnetic .
Describe the stores from a ball being thrown into the air.
Chemical energy store in the muscles-mechanical working-kinetic energy of the ball and arm-mechanical working, gravitational potential energy store of the ball.
What is the principle of the conservation of mass?
That energy cannot be created or destroyed it can only be moved from one store to another.
What is a closed system?
Energy being the same before and after the energy is transferred to another store: eg, 30J of gravitational potential energy=30J of kinetic energy
Energy transferred = work done true or false?
True
Word equation for work done is?
Work done = force x distance
Symbol equation for work done?
W=Fs:eg,
F-W=Fs
I-W=50Wx5M
F-W=50x5
A-W=250J
What do we measure work done in?
Joules or J
What do we measure force in?
Neutons or N
What do we measure distance in?
Metres or M
Symbol equation for weight?
W=mg
W=weigh (N)
M=mass(kg)
G=gravity(9.8)
Equation for gravitational potential energy?
Eg=mgh
Energy= mass x weigh x height
What is the GPE of a 70kg person being lifted up 50 cm by their friend
343j
Eg=mgh
Eg=70 x 9.8x 50cm
Eg= 70 x 9.8 x 0.5
Eg=343j
Equation for kinetic energy?
Ek=0.5 x m x v2
Kinetic Energy =0.5 x mass x velocity squared(2)
What’s the equation for Elastic potential energy ?
Ee=0.5 x k x e2
Elastic potential energy =0.5 x spring constant x extension
