Question

A 100 watt bulb operates in a 220 v circuit . find the current through the bulb and its resistance


please with step by step​

Answer 1

Given :-

A 100 watt bulb operates in a 220 v circuit.

To Find :-

( i ) Find the current through the bulb.

( ii ) Find its resistance.

Answer :-

( I ) 5 / 11 A

( ii ) 484 Ω

Solution :-

Given ,

P = 100 w

V = 220 v

•°• current ( I ) = P / V

= 100 / 220 A

= 5 / 11 A

= 5 / 11 A

And ,

Resistance ( R ) = V / I

= 220 / ( 5 / 11 ) Ω

= 220 × 11 / 5 Ω

= 44 × 11 Ω

= 484 Ω

Answer 2

$\bold{GIVEN}$

Power of bulb = 100 W

Potential difference = 220V

Let I be current and R be resistance,

We know,

RESISTANCE IS THE OBSTRUCTION OFFERED INTO THE PATH OF CURRENT.

FOR RESISTANCE :-

$\boxed{ \mathsf{P = \dfrac{V^{2}}{R}}}$

On placing values,

$\mathsf{R = \dfrac{V^{2}}{P}}$

$\mathsf{R = \frac{220^{2}}{100}}$

$\mathsf{R = \dfrac{220 \times 220}{100}}$

$\boxed{ \mathsf{R =484 ohm}}$

FOR CURRENT

CURRENT IS THE RATE OF FLOW OF CHARGE.

We know,

$\boxed{ \mathsf{V = IR}}$

On placing values,

$\mathsf{220 = I \times 484 }$

$\mathsf{ \dfrac{220 }{484} = I}$

$\boxed{ \mathsf{ 0.45 A= I}}$