In fig 9 the value of R is
Attached Figure / Diagram
A
3Ω
B
4Ω
C
5Ω
D
6Ω
Verified Correct Answer: D.
Physical Principles & Numerical Solution
From Ohm's law, V = IR
But R = total resistance of the circuit.
12 = 2( 3 + \(R_{parallel}\))
12 = 2(3 + \(\frac{6R}{6 + R}\))
6 = \(\frac{18 + 3R + 6R}{6 + R}\)
36 + 6R = 18 + 9R
9R - 6R = 36 - 18
3R = 18
R = \(\frac{18}{3}\) = 6 \(\Omega\)
Source: Myschool Past Questions Archive (Record #41650)