Question

an electric lamp is marked 100 w , 220 v. it is used for 5 hours daily. calculate its resistance while glowing and energy consumed in kwh per day.

Answer 1

So, we have been given: Power= 100 w, Voltage= 200 and Time= 5 Hrs.

We know that Power= V*V/R

100= 220*220/R= 48400/R

R=484 Ohms.

There are 24 hours in a day. The energy consumed per day will be:

Energy= V*V/R multiplied with Time

So, Energy=  48400/484 multiplied with 24 Hours

We get Energy as 2400 Joules.

[Hope this Helped!]