Two electric bulbs of 100 W each is used for 10 hours in the month of June. Write the following steps in sequential order to find the numbe of units of electricity consumed in the month of June.
(A) The number of units of electricity consumed by both bulbs in the month of June is the total elec-trical energy consumed by bulbs expressed in W h divided by 100 W h .
(B) Note the rated power of each electric bulb, time of electrical consumption of each bulb per day from the given data.
(C ) We know, one electrical unit `= 1 kW h` or `1000 W h`.
(D) Calculate the amount of electrical energy con-sumed by both the bulbs in the month of June using, (sum of the electrical power of both the bulb) `xx` (time of consumption in one day) `xx 30` days.

Options

A. BACD
B. ABCD
C. BDCA
D. DCBA

Answer

C

Explanation

The power of electric bulb, `P = 100 W`.
The time for which bulb utilieses electric power per day `= 10` h.
In the month of june, `t = 10 h xx 30` days `= 300 h`.
The electric energy consumed by a bulb is `= P xx t`
`= 100 xx 300 = 32 xx 10^(4) W h`
`= 30 k Wh`
The total energy consumed by both the bulbs,
`E = 2 xx 20 kWh = 60 kW h`.
`:.` The number of electric units `= 60` units.
`(ne 1 "unit" = 1 kW h)`