Question

Please answer to this question
class 10th ELECTRICITY
SEE THE ATTACHMENT ☝️☝️​

Answer 1

Given :

Equivalent resistance = 15Ω

To Find :

➳ Resistance of each resistor.

➳ Equivalent resistance if all three are connected in parallel$.$

SoluTion :

◈ Equivalent of left part (parallel) :

➝ 1/Rp = 1/R¹ + 1/R²

➝ 1/Rp = 1/R + 1/R

➝ Rp = R/2

◈ Net equivalent of circuit (series) :

➝ Req = Rp + R³

➝ Req = R/2 + R

➝ Req = 3R/2

ATQ,

➝ Req = 15

➝ 3R/2 = 15

➝ R = 10Ω

Resistance of each resistor = 10Ω

Eq. resistance if all three are connected in parallel :

⇒ 1/Req = 1/R¹ + 1/R² + 1/R³

⇒ 1/Req = 1/10 + 1/10 + 1/10

⇒ Req = 10/3

⇒ Req = 3.33Ω