Kenetic Energy Flashcards
Do stationary object have kinetic energy
No
What is kinetic energy
The energy stored in moving objects
Moving car energy changes
Chemical energy - in petrol
Kinetic energy- moving
What are we doing when we stretch a spring
We are applying a force to change the length of the spring
What is it called when you apply a force
Doing work
What energy store does a spring have
Elastic potential energy
What is the stretch of a spring called
Extension
On a graph extension and force
Directly proportion
Why is it no longer directly proportional
Too much weight has been added the spring has reached limit of proportionality
Eq: elastic potential energy
J joules
Eq: Spring constant
N/m
Eq: Extension
M
Eq: kinetic energy
J Joules
Eq: Mass
Kg
Eq: Speed
M/S
The power output of the turbine is directly proportional to the kinetic energy of the air passing the blades each second. Describe the effect on the power output when the wind speed is halved 
Mass of air passing the turbine blades is halved which decreases kinetic energy by a factor of two. Decrease in the kinetic energy by a factor of four. So the kinetic energy decreases by a factor of eight.
As the person moves down the zip wire her increase in kinetic energy is less than her decrease in gravitational potential energy why
Friction between pulley and zip wire causes thermal energy to be released to surroundings
