Chapter 6: Energy Transformations and Energy Transfers - IGCSE Physics

What kind of energy is stored inside your muscles?

Chemical energy

What kind of energy is inside food

Chemical energy

What kind of energy does a moving object have?

Kinetic energy

What kind of energy does an object have when it is lifted up?

Gravitational potential energy

What kind of energy does fuel contain?

Chemical energy

What kind of energy does a battery contain?

Chemical energy

What kind of energy is present in an electric circuit?

Electrical energy

What kind of energy is stored in uranium?

Nuclear energy

What kind of energy is stored inside a stretched rubber band?

Strain energy; elastic energy

What kind of energy is stored inside a hot object?

Internal energy

What kind of energy comes out of a hot object?

Thermal energy; heat

What are the units of energy?

joules (J)

Energy cannot be ____________ or ______________

created, destroyed

Wasted energy usually ends up as _____________

Heat/thermal energy

The other common form of wasted energy is _____________

sound

Which word means the fraction of the energy that ends up as useful energy?

efficiency

Write down the equation for efficiency in terms of energy, if we want the answer as a percentage?

useful energy output/energy input x 100%

Write down the equation for efficiency in terms of energy, if we want the answer as a decimal?

useful energy output/energy input

Write down the equation for efficiency in terms of power, if we want the answer as a percentage
?

useful power output/power input x 100%

Write down the equation for efficiency in terms of power, if we want the answer as a decimal?

useful power output/power input

Which units do we use for efficiency, if we give the answer as a decimal instead of a percentage?

No units

In the equation for gravitational potential energy, which direction does height have to be measured in?

g.p.e. = m x g x h

In the equation for gravitational potential energy, which direction does height have to be measured in?

vertically

In this equation, if you put 'h' as the change in height, what value will your equation actually calculate?

Change in g.p.e

Write down the equation for kinetic energy in symbols.

k.e = 1/2mv2

In the symbol equation for kinetic energy, what does 'v' mean?

speed