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3 years ago

A "590-W" electric heater is designed to operate from 120-V lines.

Physics

1 answer:

lukranit [14]3 years ago

7 0

Answer:

a) 24.4 Ω

b) 4.92 A

c) 495.9 W

c. It will be larger. The resistance will be smaller so the current drawn will increase, increasing the power.

Explanation:

The formula for power is:

P = IV

where,

P = Power of heater = 590 W

V = Voltage it takes = 120 V

I = Current Drawn = ?

Therefore,

590 W = (I)(120 V)

I = 590 W/120 V

I = 4.92 A

From Ohm's Law:

V = IR

R = V/I

Therefore,

R = 120 V/4.92 A

R = 24.4 Ω

For constant resistance and 110 V the power becomes:

P = V²/R

Therefore,

P = (110 V)²/24.4 Ω

P = 495.9 W

If the resistance decreases, it will increase the current according to Ohm's Law. As a result of increase in current the power shall increase according to formula (P = VI). Therefore, correct option is:

c. It will be larger. The resistance will be smaller so the current drawn will increase, increasing the power.

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Where,

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