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2 years ago

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A 12-V DC automobile head lamp is to be used on a fishing boat with a 24-V power system. The head lamp is rated at 50 W. A resis

tor is to be connected in series with the lamp to permit it to operate on 24 V. What should be the resistance and power rating of the resistor?

1 answer:

spin [16.1K]2 years ago

8 0

Answer:

The resistance is $R = 2.88 \ \Omega$

Explanation:

From the question we are told that

The voltage rating of the headlamp is $V_1 = 12 \ V$

The voltage of the power system is $p = 24 \ V$

The power rating of the headlamp is $P = 50 W$

Generally the power which the resistor dissipates is mathematically represented as

$P = V_L * I$

=> $50 = 12 * I$

=> $I = 4.1667 \ A$

Generally the resistance is

$R = \frac{V_1 }{I}$

$R = \frac{12 }{4.1667}$

$R = 2.88 \ \Omega$

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