Difference between Power and Energy
Power
1.) Power gives the illustration about the strength of object.
2.) How much time is required to do certain work decides the power of object/machine/person.
3.) Power is defined as the rate of doing work.
∴ Power = Work/Time
∴ P = W/t
4.) SI unit of power is watt (W)
5.) When 1 joule of work is done by object in 1 second, the power of object is termed as 1 watt.
6.) Since ‘watt’ is small unit of power, it is used in larger scale as kilowatt, where
1 kilowatt =1000 watt
7.) Horse power (hp) is also a unit of power, where 1 hp= 746 watt.
Energy
1.) Energy gives the illustration about the ability of application of force.
2.) How much force can be applied is decided by the energy, hence energy can also be termed as the driving force.
3.) Energy is defined as the capacity of doing work.
∴ Amount of work done = energy
∴ Energy = F.s
4.) SI unit of energy is joule (J).
5.) When 1 newton of force applied on object displaces it by 1 m, then the work done or energy spent can be equal to 1 joule.
6.) CGS unit of energy is erg, where 1 joule = 107 erg.
7.) Calorie is also another unit of energy, where 1 cal = 4.2 joule.