Question

1) A bulb is rated at 220v-100W. What is its Resistance? 5 such bulbs burn for 4
hours. What is the Electrical energy Consumed.​

Answer 1

Explanation:

the electricity consumed is from 1010 volt to 500volts

Answer 2

We know that for an electric appliance

P = V2/R

or

resistance will be given as

R = V2 / P

now, here

P = 100 W

V = 200 volts

so,

R = 2002 / 100

= 40000 / 100

thus, resistance of the bulb is

R = 400 Ω

..

now, electric energy consumed will be

E = number of units x power of each unit x time = n x P x t

here,

n = 5

P = 100 W

t = 4 hours

so,

E = 5 x 100 x 4

thus,

E = 2000 Wh = 2 kWh

..

the total cost of electricity = total unit of energy consumed x cost per unit

= 2kWh x 0.5 Rs/kWh

thus,

total cost (daily) = Rs. 1

and

monthly cost = total daily cost x number of days in month

= Rs. 1 x 30 days

or

monthly cost = Rs. 30