A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistance, which may be used separately, in series, or in parallel. What are the currents in the three cases?

Asked by Vishal kumar | 2 years ago |  523

1 Answer

Solution :-

Case (i) When coils are used separately

Using Ohm’s law, we can find the current flowing through each coil as follows:

\(I= \frac{V}{R}\)

Substituting the value, we get

\( I=\frac{220\,V}{24\,\Omega}=9.166\,A\)

9.166 A of current flows through each resistor when they are used separately.

Case (ii) When coils connected in series,

The total resistance in the series circuit is 24 Ω + 24 Ω = 48 Ω The current flowing through the series circuit is calculated as follows:

\( I=​​\frac{V}{R}=\frac{220\,V}{48\,\Omega}=4.58\,A\)

Therefore, a current of 4.58 A flows through the series circuit.

Case (iii) When coils connected in parallel

When the coils are connected in parallel, the equivalent resistance is calculated as follows:

\( R = \frac{24\times24}{24+24}=\frac{576}{48}=12\,\Omega\)

Using Ohm's law, the current flowing through the parallel circuit is given by 

\( I=​​\frac{V}{R}=\frac{220\,}{12\,}=18.33\,A\)

The current in the parallel circuit is 18.33 A.

Answered by Shivani Kumari | 2 years ago

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