Work And Energy Flashcards
What is work?
Work is done whenever energy is transferred from one store to another
What is work a measure of?
Energy transfer
How is work calculated?
Work = force x distance moved
When work is done will the total energy change?
No, the total energy at the start must equal the total energy at the end of the action
What might change from the start of the activity to then end?
The type of energy
How can an object posses energy ?
Because of its motion (kinetic energy)
Position (gravitational potential energy)
Deformation (elastic energy)
Name so,e modern safety features of cars?
air bags and crumple zones
Why do air bags and crumple zones increase chance of survival ?
Both features change shape during a collision, this allows work to reduce the kinetic energy of the passengers to be done over a long distance.
The longer the distance the work is done over the smaller the force on the passengers will be.
Name some efficient ways of reducing energy losses
Aerodynamic losses
Rolling resistance
Idling losses
Inertial losses
What are inertial losses?
Reduce the mass of vehicles so that less force is needed to move them
What is rolling resistance ?
Use materials in tyres that don’t heat up as much as they get squashed
