4. A fan of power 50 W is used 8 hours per day and a TV of power 40 W is used 6 hours per day. What is the energy consumption of a fan and TV per month of 30 days?
640 Wh
12000 Wh
7200 Wh
19200 Wh
Answers
Answer:
(D) 19200 watt hours
Explanation:
Given :
- Power of the fan = 50 watts for 8 hours
- Power of the TV = 40 watts for 6 hours
To find :
- Monthly consumption
Energy consumed by fan = 50×8 = 400 Watt hours
Energy consumed by TV = 40×6 = 240 watt hours
Daily consumption = 400+240 = 640 Watt hours
Monthly consumption = 640×30
Monthly consumption = 19200 watt hours
The option d is correct and hence 19200 watt hours is the energy consumed
Answer :
1 tube light consumes power = 40 W
There fore ,3 tube lights consume power = 3 x 40 W= 120 W
3 tube lights are kept on for five hours. So, consumption of power by 3 tube lights.
= 5 x 120 W = 600 W-------(1)
1 fan consumes power = 80 W
Therefore, 2 fans consume power = 2 x 80 W= 160 W 2 fans are kept on for 12 hours. So, consumption of power by 2 fans.
= 12 x 160 W = 1920 W-----------(2)
TV draws power = 60 W
TV is kept on for 5 hours = 5 x 60 W = 300 W---------(3)
Therefore, In One day consumption of power = (1) + (2) + (3)
= 600 W + 1920 W + 300 W
= 2820 W = 2.820 KW
Therefore, Total consumption of power in 30 days at Rs. 3 per KW
= 2.820 x 30 x 3 = Rs. 253.80