Q8. An electric bulb is marked 18watt-240 volt. If it is used across 240 V power line for one hour daily, calculate the number of days to consume 1 unit of electric energy.

 

Asked by Khekaleaarya | 7th Jul, 2020, 08:35: PM

Expert Answer:

Power, P = 18 W 
V = 240 V 
It is given that electric bulb is used daily for 1 hour across 240 V power line. 
Thus, 
Electricity consumed is given as, 
E  = Pt 
1 unit = 1 kwh = 3.6 x 106 J 
3.6 x 106 = 18 x n x 1h x 60 min x 60 s
where, n = number of days
Thus,
n = 55.5 days 
 

Answered by Shiwani Sawant | 7th Jul, 2020, 11:23: PM