To proceed to the question first we need to understand the meaning of 1 unit that is, 1 unit is simply equal to 1kiloWatthour or when 1000 Watt of power is consumed in 1 hour.
Now we are given with the power(P) of the immersion rod which is 1500 Watt and we are given with the time limit for each day which is 3 hours and the number of days for which the rod was used which is 30 days, so let’s calculate the total time(t) in the question, which is 3 hours × 30 days = 90 hours, we have converted into hours because of units used in power above.
We are also given with the cost of 1 unit which is Rs. 5 hence expense of 1 kWh energy and we have to calculate the amount of money spend in the month for that we have to calculate the amount of energy used in kWh.
Rs. 5 = 1000Watt × 1 hour = 1kwh
Therefore we have 1500 watt power, so,
1.5 × Rs. 5 = 1500 Watt × 1 hour
We also have 90 hours of using the rod, so,
90 × 1.5 × Rs. 5 = 1500 Watt × 90 hours
Therefore the amount of money spend in the month will be Rs. 675.
Rate this question :