What is the cost of electrical energy consumed at Rs 5 per unit in the above case
Answers
Step 1:-The bulbs: Eight 100 W for 40 hr. = 8 100 20 W for 1 hr
= 16 1000 W for 1 hr
= 16 kW for 1 hr
Step 2:- Heater:500V for 20 hrs = 500 W 1 hr
= 5000 W for 1 hr
= 5 kW for 1 hr
Step 3:- Total consumption = (16+5) kW for 1 hr
= 21 kW for 1 hr
Step 4:- Cost of 1 kW for 1 hr = Rs. 2 per kWhr
Cost of 42 kW for1 hr = Rs. 2 x 21 = Rs. 42/‑
Total units = 1.28 + 1.6 + 0.4 + 4.8
= 8.08
Cost of 1 unit = rs.5
Total cost of unit = 8.08 × 5
= 40.4 rs.