Question

final energy in kilo watt hours consume in by two devices of power 500 watt each

Answer 1

Power of 1 device = 500 W

Power of 2 devices = 500*2 = 1000 W or 1 kW

Let the time be 't' hrs.

Then, Energy = P*T = 1*t = 1t kW H or t kwH or t units.

Hope it helps.