Energy Flashcards
What is energy?
Energy is the ability to do work . Measured in Joules ( J )
What is an energy store ?
How energy is kept by an object until it’s ready to be used .
What is an energy transfer?
How energy is moved from one object or place to another
What is the conversation of energy?
Energy cannot be created or destroyed. Only transferred from one place to another.
What does dissipate mean ?
When energy is transferred to the thermal store of the surroundings and wasted
What is a Joule ?
The unit of energy. Amount of energy transferred per second.
What is efficiency?
It tells us how much energy is transferred to useful and wasted energy
What are the 8 energy stores ?
Magnetic, thermal, kinetic, gravitational potential, electrostatic, chemical, elastic potential, nuclear
Describe the energy transfer that occurs when a ball falls to the ground
Gravitational force - kinetic
What is the formula for efficiency?
Useful energy output ÷ total energy input
Explain why having a more efficient motor increases the top speed of the car?
Less energy is wasted, more energy is transferred to useful kinetic energy
How would friction effect efficiency?
Friction dissipates more energy to the thermal energy store of an appliance, reducing total useful energy
If we want to cool a building, should it be made out of materials made of high or low conductivity. Explain why
High conductivity as energy is transferred quicker
What does ‘ work ‘ mean?
When energy is transferred from one store to another
What is a system ?
An object or group of objects
