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3 years ago

8

A resistor with resistance R is connected to a battery that has emf 13.0 V and internal resistance r = 0.350 Ω . For what two va

lues of R will the power dissipated in the resistor be 81.0 W ?

1 answer:

makvit [3.9K]3 years ago

8 0

Answer:

R = 1,746 Ω

Explanation:

The power dissipated in the circuit is

P = V I = V² / R

Let's find the current

R = V² / P

Let's calculate

R = 13²/81

R = 2,096 Ω

This is total resistance

R_total = R + r

R = R_total - r

R = 2,096 -0,350

R = 1,746 Ω

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