Question

a) what is power?

b) define it's unit?

c) what is realation between 1Kwt and J. find the relationship?

d) A lamp consumes 1000J of electric energy in 10s. what is its power

Answer 1

In physics, power is the rate of doing work, the amount of energy transferred per unit time. Having no direction, it is a scalar quantity. In the International System of Units, the unit of power is the joule per second (J/s), known as the watt in honour of James Watt, the eighteenth-century developer of the steam engine condenser. Another common and traditional measure is horsepower (comparing to the power of a horse)
The relation between kilowatt hour and joule is.. 
1 kWh = 3,600,000 J

And 

1 kWh = 3·6 MJ (mega joules)
3rd question_
given that , 
   work done = 1000 J
   time taken = 10 sec.
   Power = ?
              = w/t 
              = 1000/10
               = 100w