Question

a heating appliance has a resistance of 115 ohm. if 2A current flows through it, what is the power of the appliance?
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Answer 1

Current , I = 2 A

Resistance, R = 115 ohm

DIRECT FORMULA OF POWER

Power, P = I²R

$P = {(2 )}^{2} \times 115 \\ \\ P = 4 \times 115 \\ \\ P = 460 \: watt$

The power of the appliance is 460 watt

ALTERNATIVE METHOD

According to ohms law, The potential difference, V = I R

V = 2 × 115

V = 230 volt

Power = V× I

$P = 230 \times 2 \\ \\ P = 460 \: watt$

Answer 2

Answer:

The power of appliance = 460 W

Explanation:

Given,

Resistance of appliances, R = 115 ohms

Current of appliance, I = 2 A

Let the potential difference of the appliance be V. Then,

By ohm's law, we know that,

Resistance = Potential Difference / Current

=> R = V/I

By applying values, we get,

=> 115 = V / 2

=> V = 230

Hence, potential difference of the appliance = 230 V

Now, we know that,

Power = Potential Difference × Current

=> P = V × I

=> P = 230 V × 2 I

=> P = 460 VI

=> P = 460 W

Henceforth, the power of appliance = 460 W