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Three electric cells each of e.m.f 1.5V and internal resista...

Three electric cells each of e.m.f 1.5V and internal resistance of 1.0\(\Omega\) are connected in parallel across an external resistance of \(\frac{2}{3}\)\(\Omega\). Calculate the value of the current in the resistor

A.

0.5 A

B.

0.9 A

C.

1.5 A

D.

4.5 A

Correct answer is C

E.m.f = 1.5

r = \(\frac{1 \times\ 1 \times 1}{(1 \times\ 1) + (1 \times\ 1) + (1 \times\ 1)}\)

r = \(\frac{1}{3}\)\(\Omega\)

I = \(\frac{E.m.f}{r + R}\)

I = \(\frac{1.5}{\frac{1}{3}\ + \frac{2}{3}}\)

I = 1.5A