Flashcards
P1 Conservation and Dissipation of Energy (AQA)
Flashcards do conjunto (14)
- 1What is the principle of Conservation of Energy?That "Energy can not be created or destroyed".
- 2A ride is fired into the sky by rubber bands of a catapult. Explain the changes to the energy stores as the ride moves upwards.1. It's elastic potential energy is increased, due to the stretch of rubber bands.
2. Kinetic energy increases due to fast movement of ride.
3. Gravitational potential increases due to height off ground. - 3Work done, (J) = (Work is done on the object by the force)Force Applied x Distance moved
(Newtons,N) (metres, m) - 4Calculate the work done when a force of 20N makes an object move 4.8m in the direction of force.Force x Distance.
20N x 4.8m = 96J - 5Change in G.P.E (J) =weight, (N) x change in height (m)
OR
mass (kg) x g.f.s (N/kg) x change in height (m) - 6Kinetic Energy (J) =1/2 x Mass (kg) x Speed² (m/s²)
- 7elastic potential energy (J) =1/2 x spring constant (N/m) x extension² (m²)
- 8A car moving at a constant speed has 360,000J in its kinetic energy store. When brakes are applied, it stops in 100m. Calculate the force that stops the car.Work done ÷ Distance moved.
360,000J ÷ 100m = 3,600N - 9Calculate the kinetic energy stored in a vehicle of mass 500kg moving at a speed of 12m/s.Kinetic energy= 1/2 m v²
0.5 x 500kg x (12m/s)²
= 36,000J - 10Wasted energy =Energy that is not usefully transferred.
Eventually transferred to the surroundings which become warmer. - 11Efficiency =Useful output energy transferred ÷
total input energy supplied. - 12Examples of improving Efficiency:- Lubricate moving parts to reduce friction.
- Cut out noise, reduce vibration.
- in circuits, use wires with little resistance. - 13Power (W) =energy transferred (J) ÷ time taken (s)
- 14power wasted =total power in - useful power out.
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- GCSE Physics FlashCards sobre P1 Conservation and Dissipation of Energy (AQA), criado por Mia Lynas em 01-03-2018.
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- Mia Lynas
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