-Energy and energy resources Flashcards
What are the different types of energy stores?
-gravitational potential energy
-elastic potential energy
-kinetic energy
-thermal energy
-chemical energy
What is a system?
how an object behaves or how objects interact.
What is work done?
The amount of energy a force exerts on an object
What is the formula for work done?
Work done (J) = force (N) x distance (m)
Why and how may machinery be improved to limit friction.
machinery should be adjusted to limit the amount of friction as friction means that there is an unnecessary energy transfer going on, which wastes energy which is expensive. To overcome this, machinery may be changed to be stream lined / narrow to avoid air resistance, and may be lubricated with oil to reduce friction between moving parts.
What’s the formula for kinetic energy?
kinetic energy (J) = ½ x mass (kg) x speed ² (m/s)
What’s the formula for elastic potential energy?
elastic potential energy (J) = ½ x spring constant (N/m) x extension ²
What is power?
The amount of energy transferred in a certain time
What is the formula for power?
Power (W) = energy transferred (J) ÷ time taken (s)
In terms of radiation, describe an object that is:
-at a constant temperature
-cooling
-warming
-the amount of radiation being absorbed is the same as being emitted
-the amount of radiation being absorbed is less than what is being emitted.
-the amount of radiation being absorbed is more than what is being emitted.
Explain the correlation between an objects colour it emits and its temperature:
the hotter an object is, the shorter the wavelengths it emits, meaning that the hotter something gets the brighter they emit.
Give ways on how a house can be better insulated:
-cavity wall insulation
-loft insulation
-double glazed windows
-aluminium foil behind radiators
How does a power station generate electricity?
A fuel is used to create steam out of water, normally using fossil fuels or biofuels. The steam is fed through a tunnel of turbines, which propels them in a generator to make electricity. The steam is released as well as greenhouse gases.
