Food and fuels like oil, gas, coal etc are concentrated stores of

A mixture of methane and carbon dioxide with energy content is

The unit of moment of force is

The force which opposes one surface moving over another is

A device which can turn about a point is called

A quantity which has both magnitude and direction is

A quantity which has only magnitude is called

The energy possessed by a body by virtue of its motion is called

The energy which can not be replaced when once used up is

In solar energy, which device is used to transfer energy ?