Question

Find the voltage of power supply to which a bulb of rating 200W- 220V is connected to consume energy at the rate of 100 J/s.​

Answer 1

Answer:

The Power P = 100 W and Voltage V = 220 V. So, current I is I = P/V = 100/220 = 0.45 A. When the supplied voltage is 110 V, the power consumed will be P=VI = 110 * 0.45 = 50 W. Hence, the power consumed when operated at 110 V is 50 W.

Answer 2

• Voltage is 110 volts.

According to the Question

It is given that,

• Power of bulb ,P = 200W
• Potential Difference ,V = 220v
• Rate of consumption of energy = 100J/s

we have to calculate the voltage supply to which a rating 200 w bulb .

Here the energy consumed at the rate of 100J/s .

is power of bulb .

Means P' = 100 W

Firstly calculating the Current in 1st case

• P = VI

On substituting the value we get

↠ 200 = 220 × I

↠ I = 200/220

↠ I = 0.90 A or 10/11 A

here the current supply to bulb is constant .

Now, calculating the voltage in 2nd case

Let the voltage at 2nd case is V'

• P' = V' I

On substituting the value we get

↠ 100 = V' × 10/11

↠ V' = 100×11/10

↠ V' = 110v

• Hence, the voltage is 110 volts.