Question

A parallel combination of three resistors takes a current of 5a from a 20 v supply .If the resistors are of 10 ohm and 8 ohm find the value of tgree resitors

Answer 1

Answer:

Equivalent resistance = V / i

= 30 V / (7.5 A)

= 4 Ω

In parellel arrangement

1/Req = 1/R₁ + 1/R₂ + 1/R₃

1/R₃ = 1/Req - (1/R₁ + 1/R₂)

1/R₃ = 1/4 - (1/10 + 1/12)

R₃ = [1/4 - (1/10 + 1/12)]^-1

R₃ = 15 Ω

Resistance of third resistor is 15 Ω

Answer 2

Answer:

Equivalent resistance = V / i

= 30 V / (7.5 A)

= 4 Ω

In parellel arrangement

1/Req = 1/R₁ + 1/R₂ + 1/R₃

1/R₃ = 1/Req - (1/R₁ + 1/R₂)

1/R₃ = 1/4 - (1/10 + 1/12)

R₃ = [1/4 - (1/10 + 1/12)]^-1

R₃ = 15 Ω

Resistance of third resistor is 15 Ω