Question 209: Current Electricity

Question

The combination of two identical cells, whether connected in series or parallel combination provides the same current through an external resistance of 2$$\Omega$$. The value of internal resistance of each cell is

Accepted Answer

From diagram
$${i_p} = {E \over {2 + {r \over 2}}}$$ and $${i_s} = {{2E} \over {2 + 2r}}$$
given $${i_p} = {i_s}$$
$${1 \over {2 + {r \over 2}}} = {1 \over {1 + r}}$$
$$1 + r = 2 + {r \over 2}$$
$$r = 2\,\Omega $$

Answer

2$$\Omega$$

Answer

4$$\Omega$$

Answer

6$$\Omega$$

Answer

8$$\Omega$$

Current Electricity

The combination of two identical cells, whether connected in series or parallel combination provides the same current through an external resistance of 2$\Omega$. The value of internal resistance of each cell is

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