Q.
For a cell, the graph between the potential difference $(V)$ across the terminals of the cell and the current $(I)$ drawn from the cell is shown in the figure. The e.m.f. and the internal resistance of the cell are
A) $2V,\ 0.5\Omega$
B) $2V,0.4\Omega$
C) $> 2V,05\Omega$
D) $> 2V,\ 0.4\Omega$
Explanation
(b) E.m.f. is the value of voltage, when no current is drawn from the circuit so $E = 2V$.
Also $r = slope = \frac{2}{5} = 0.4\Omega$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.