Question

1000 W heater is used 6 hours daily and the cost of 1 unit of electricity is 40 p. how much will it cost in the month of November?

Answer 1

Step 1: Given data

1. Power of the heater, P = 1000 W
2. Total hours used by the heater in a day = 6 hours.
3. Cost of 1 unit of electricity = 40p = .4 Rs

Step 2: Calculating the total time used by the heater in the month of November.

1. Total number of days in November = 30 days.

$$\begin{gathered} TotaltimeusedbyheaterinNovember=Totalhoursuseddaily\times Numberofdaysinnovember. \\ =6hours\times 30 \\ =180hours \end{gathered}$$

Step 3: Calculating total energy consumed by the heater in November

$$\begin{gathered} Power=\frac{Totalenergyconsumed}{Totaltime} \\ Totalenergyconsumed=Power\times Totaltime \\ =1000W\times 180hours \\ =180000Wh \\ =180kWh \end{gathered}$$

Step 4: Calculating the cost of electricity.

1. $$\begin{gathered} 1kWh=1unit \\ 180kWh=180unit \end{gathered}$$

2. $$\begin{gathered} Total\cos t=Unitsofenergyconsumed\times Costperunit. \\ =180\times .4Rs \\ =72Rs \end{gathered}$$

Hence, the cost of energy for the month of November is 72 Rs.