Question

If a TV of rating 100W is operated for 6hrs per day, what is the number of units consumed in any leap year?
1) 219.6 kWh
2) 218.6 kWh
3) 215.8 kWh
4) 315.2 kWh

Answer 1

Hint:Here we have given the rating of the TV to be 100 W which is the power consumed but we haven’t been given time i.e. 100 W are consumed in how many hours, mins or seconds. In general, whenever any electrical rating is mentioned in the back of an electrical device the power rating is based on the hour. So, here 100 W means that the power is consumed in 1 hr.

Complete step by step solution:
Power consumed in one hour: 100W;
Power consumed in 6 hrs: $6 \times 100 = 600W$;
Power consumed in a day = Power consumed by TV in 6hrs = 600W;
Now, in a leap year there are 366 days instead of 365days:
For a leap year power consumed in a day: $366 \times 600 = 219,600Whr$;
Now, convert Whr to kWh by dividing the value by 1000:
For a leap year power consumed in a day: $\dfrac{{219,600Whr}}{{1000}} = 219.6kWhr$;

Final Answer:Option “1” is correct. The number of units consumed in any leap year $219.6kWhr$.

Note:Here, we don’t need to apply the formula to calculate the power of the TV, it is already given to us. We need to calculate the power consumed in a leap year. To find the power consumed for a leap year, first find the power consumed in a day and then multiply the power consumed in a day times the number of days in a leap year which is 366.