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Three cells each of emf, 1.0 V, and internal resistance, ...

Three cells each of emf, 1.0 V, and internal resistance, 2 Ω, are connected in parallel across a 3Ω  resistor. Determine the current in the resistor.

A.

0.90A

B.

0.39A

C.

0.30A

D.

0.01A

Correct answer is C

Given Data: Emf = 1v, r = 2 ohms, R = 3 ohms, I = ?

3 resistance in parallel = 1r1 + 1r21r3

1rT121212

1rT1+1+12

1rT32

cross multiply

rT23 or 0.67

E = I(R+r) 

1 = I(3+0.67)

1 = I(3.67)

1 ÷ 3.67 = I

0.27 = I

: I ≈ 0.30A