A heater coil is cut into two equal parts and only one part is used in the heater. The heat generated will now be how many times the original heat generated for the same voltage?

A. 2 times — When the coil is cut in half, the resistance of the new coil becomes half of the original. Since power is inversely proportional to resistance for a constant voltage, halving the resistance doubles the power and thus the heat generated.

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$A heater coil of resistance R is cut into two equal parts and only one part is used in the heater. The heat generated H^{'} will now be how many times the original heat generated H for the same voltage V ?$

A. $2 times$
B. $4 times$
C. $0.5 times$
D. $1 time$

Show correct answer & step-by-step solution

Correct answer: A — $2 times$

Solution

Original power P = V^{2} / R . New resistance R^{'} = R /2 . New power P^{'} = V^{2} / (R /2) = 2 (V^{2} / R) = 2 P .

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A heater coil of resistance R is cut into two equal parts and only one part is used in the heater. The heat generated H′ will now be how many times the original heat generated H for the same voltage V?

Solution

Attempt this question & track your score

More Current Electricity practice questions

$A heater coil of resistance R is cut into two equal parts and only one part is used in the heater. The heat generated H^{'} will now be how many times the original heat generated H for the same voltage V ?$