Question

.
In a house 4 lamps of 100 W and 2 fans of 160 W run for 5 hours a day. If the cost of one unit of electricity
is Rs. 10, then calculate the total cost of electricity for a month.​

Answer 1

Answer:

Units consumed in lamps = 4[100*5/1000] kWh

= 2 kWh

Units consumed in fans = 2[160*5/1000] kWh

= 1.6 kWh

Total units consumed in a day = [2+1.6] kWh

= 3.6 kWh

Total units consumed in a month = 3.6*30 kWh

= 108 kWh

If cost of 1 kWh is Rs. 10, then, the total cost of electricity at the end of the month will be = Rs. (108*10)

Rs. 1080

Hope This Helps.

Answer 2

Given:-

• Power of Lamp ,P = 100W

• Number of Lamp = 4

• Power of Fans ,P' = 160 W

• Number of fans = 2

• Cost of one Unit = Rs 10

To Find:-

• The total cost of electricity for a month.

Solution:-

There are 30 days in a month.

Power of 4 lamps = 4×100 = 400 W

•E = Pt

where

E is the energy consumed

P is the power

t is the time taken

Substitute the value we get

→ E = 400×5

→ E = 2000 Kw

→ E = 2000/1000 kWh = 2 kWh or 2 unit

Power of 2 fan = 2×160 = 320 W

• E' = Pt

Substitute the value we get

→ E' = 320×5

→ E' = 1600kW

→ E' = 1600/1000 kWh = 1.6 kWh or 1.6 Unit

Total energy consumed by appliances = 2+1.6 = 3.6 Unit

Now,

Energy Consumed by appliances in 30 days = 30 × 3.6 = 3× 36 = 108 Unit

→ Cost of 1 Unit = Rs 10

Therefore , Cost of 108 Unit = 108

8×10 = Rs1080

Therefore , Total cost of electricity for a month is Rs.1080 .