Question

calculate the monthly bill for a heater of resistance 30 ohm used on 220 volt mains it is used daily for 1 hour at the cost of 5 rupees per kiliowatt hour​

Answer 1

Given:

Resistance (R) = 30 Ω

Voltage (V) = 220 V

Time (t) = 1 h daily

Cost = ₹5 per kWh

To find:

Calculate the monthly bill for a heater.

Solution:

Power consumed (P) = V²/R

P = 220²/30 = 48400/30 =  1613.33 W

Energy consumed (E) = P × t

E = 1613.33 × 1 × 30 = 48399.9 Wh ≈ 48400 Wh = 48.4 kWh

Total bill = 48.4 × 5 = ₹242

Therefore, the total monthly bill for a heater is ₹242