A) \[2Rr/(R+r)\]
B) \[8R(R+r)(3R+r)\]
C) \[2r+4R\]
D) \[5R/2+2r\]
Correct Answer: A
Solution :
[a] In a circuit, any circuit element placed between points at the same potential can be removed, without affecting the rest of the circuit, here, by symmetry, points A, B and C are at same potential, for any potential difference between P and Q. The circuit can therefore be reduced as shown below Effective resistance \[{{R}_{eq}}=\frac{2Rr}{R+r}.\]You need to login to perform this action.
You will be redirected in
3 sec