Question

An electric bulb of 100 watt works for 4 hrs a day calculate the unit of energy consumed in 15 days

Answer 1

Power of electric bulb = 100 W = 100/1000 = 0.1 kW
Time for which electric bulb works = 4 hr / day
We have to calculate the units of energy consumed in 15 days.
Solution:
We know that,
Power = Energy consumed / Time taken
Energy consumed = Power x Time taken
Energy consumed = 0.1 x 4
Energy consumed = 0.4 k W hr
This is the amount of energy consumed in 1 day.
For calculating the amount of energy consumed in 15 days, we multiply amount of energy consumed in 1 day by 15.
So,
Energy consumed in 15 days = 0.4 x 15
Energy consumed in 15 days = 6 k W hr
This is the required solution of the numerical.
Thanks.

Answer 2

Given:

Power (p)= 100 Watts

p = 100/1000 kW

p= 0.1 kW

Time = 4 Hours

Energy consumed=p ×t


Energy consumed= 0.1 × 4

Energy consumed== 0.4 kWh( units)

Energy consumed in one day = 0.4 kWh (units)

Energy consumed in 15 days = 15 ×0.4

Energy consumed in 15 days = 6 kWh (units)

Hence, the energy consumed in 15 days is 6 kWh or 6 units.

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Hope this will help you...