Question

Have you seen an electricity meter in your home? Note down the readings on the electricity meter for two consecutive days at the same time, say Sunday 8 AM and Monday 8 AM. Now, answer the following:

1. What was the meter reading on the first day (Sunday)?
2. What was the meter reading on the second day (Monday)?
3. How many units of electricity have been used?
4. In how much time have these units been used?
5. If the rate is ₹ 5 per unit, what is the cost of electricity used during this time?
6. How can we reduce energy consumption?

Answer 1

(i) The meter reading on Sunday at 8 AM was 2450 kWh.

(ii) The meter reading on Monday at 8 AM was 2462 kWh.

(iii) 12 units of electricity have been used.

Units used = Monday's reading − Sunday's reading

= 2462 − 2450

= 12 units (kWh)

(iv) These units have been used in a time span of 24 hours (from Sunday 8 AM to Monday 8 AM).

(v) The cost of electricity used during this time is ₹ 60.

Formula:

Total Cost = Units used × Rate per unit

= 12 × 5

= 60

(vi)

• Switch off lights, fans, and appliances when leaving a room.
• Use energy-efficient LED bulbs instead of old filament bulbs or tubelights.
• Maximize the use of natural daylight during the daytime.
• Unplug chargers and electronic devices when they are not in use to avoid standby power loss.