Find the value of current I drawn from the cell.
(a) Calculate the current I.
(b) Calculate the terminal voltage.

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(a) As, the two 15Ω resistors are in series
So, Rs = 15 + 15 = 30Ω
Now, Rs (i.e., 30Ω) and 30Ω are in parallel,
$$\begin{aligned}\therefore \frac{1}{\text{R}_p} = \frac{1}{30} + \frac{1}{30} \\[1em] = \frac{2}{30} \\[1em] = \frac{1}{15}\end{aligned}$$
∴ Rp = 15Ω
Now, total resistance of the circuit = 2Ω + 15Ω = 17Ω
$$\begin{aligned}\text{I} = \frac{\text{emf}}{\text{total resistance}} \\[1em] = \frac{3.4}{17} \\[1em] = 0.2 \text{ A}\end{aligned}$$
∴ Current I = 0.2 A
(b) Terminal voltage [V] = emf - Ir
= 3.4 - [0.2 x 2] = 3.4 - 0.4
= 3 V
Hence, terminal voltage = 3 V