Question 632: Current Electricity

Question

A cell of emf 4 V and internal resistance 0.5 $$\Omega$$ is connected to a 7.5 $$\Omega$$ external resistance. The terminal potential difference of the cell is

Accepted Answer

From Kirchhoff's loop law :
$$V - Ir - IR = 0$$
$$ \Rightarrow I = \left( {{V \over {r + R}}} ight)$$
Terminal potential difference across cell,
$${V_{AB}} = IR$$
$${V_{AB}} = {{RV} \over {r + R}}$$
$$ = {{7.5 	imes 4} \over {0.5 + 7.5}} = 3.75\,V$$

Answer

0.375 V

Answer

3.75 V

Answer

4.25 V

Answer

4 V

Current Electricity

A cell of emf 4 V and internal resistance 0.5 $\Omega is connected to a 7.5 \Omega$ external resistance. The terminal potential difference of the cell is

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