An electric oven with 2 kW power rating is operated in a domestic electric circuit (220 V) that has a current rating of 5 A. What result do you expect? Explain.

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Chapter 12

NCERT

Class 10

Science

Solutions

2. An electric oven with 2 kW power rating is operated in a domestic electric circuit (220 V) that has a current rating of 5 A. What result do you expect? Explain.

Question:

An electric oven with 2 kW power rating is operated in a domestic electric circuit (220 V) that has a current rating of 5 A. What result do you expect? Explain.

Answer:

Here I = ?, R = ?, P = 2kW = 2 × 10³ W, V = 220 V

Using formula, P = V² / R

⇒ R = V² / P

R = (220 X 220) / (2 X 10³)

R = (484 X 10²) / (2 X 10³)

R = 242 X 10^-1

‍

Using formula V = IR

I = V/R

I = 220 x 10/ 242

I = 2200 / 242

I= 9.09A

‍

The current (9.09 A) exceeds the fuse rating (5 A) of the given circuit. Due to this, the fuse is broken due to the high flow of current through the circuit.

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