Question

22. How much current will an electric bulb draw from 220 V source if the resistance of the bulb is 1200Ω? If in place of bulb, a heater of resistance 100 Ω is connected to the sources, calculate the current drawn by it.

Answer 1

Given :-

An electric bulb draw from 220 V source if the resistance of the bulb is 1200Ω

To Find :-

Current

Solution :-

We know that

V = IR

Here

V = Voltage

I = Current

R = Resistance

220 = (I)1200

220/1200 = I

22/120 = I

0.18 = I

Therefore

Current is 0.18 A

Now, When heater connected

V = I'R'

220 = I'(100)

220/100 = I'

22/10 = I'

2.2 = I

Current is 2.2 A

Answer 2

Solution:-

V (Potential Difference)⇒ 220V

R (Resistance) ⇒ 1200Ω

By Ohm's Law,

V ⇒  IR

220 ⇒  I × 1200

I ⇒ $\frac{220}{1200}$ ⇒  0.18

I ⇒ 0.18 Ampere

Now,

Resistance of heater ⇒ 100Ω

By Ohm's Law,

V ⇒ IR

220 ⇒ I × 100

I ⇒ $\frac{220}{100}$ ⇒ 2.2

I ⇒ 2.2 Ampere

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