Question

a geyser of 2.5 kw is used for 8 hrs. calculate monthly consumption (30 days) of electric energy.also calculate the cost of electricity units if rate per unit is rupees 3.5​

Answer 1

Here it's mentioned that geyser is used 8 hrs per day. Hence forget about 24 hrs and focus on those 8 hrs given.

Solution: E = Pt

→ E = 2.5 kW × 8h

→ E = 20 kWh

Consumption in 1 day = 20 kWh

Consumption in 30 days = 30 × 20 kWh

= 600 kWh

Hence 600 units on energy is consumed (1 kWh = 1 unit)

Cost = 600 × Rs 3.5

= Rs. 2100

Answer: Cost is Rs 2100 for using geyser for 30 days (a month).