a) How a kilowatt and kilowatt-hour differ? Convert 1 kWh into joules.  

                                                                                         OR

A bulb is rated 5 V and 500 mA. Calculate the rated power and resistance when it is lighted.

a) A kilowatt (kW) is a large unit of electric power. Whereas kilowatt hour (kWh) is the commercial unit of electric energy. Though both are interrelated units of measurement, the important distinction between a kWh vs kW is that a kWh reflects the total amount of electricity used, whereas a kW reflects the rate of electricity usage. Technically, the major difference is that a kWh is a measurement of energy, whereas a kW is a measurement of power, 1 kWh = 3.6 × 10⁶ joules

                                                                                         OR

b)