Question

The pd a cross terminals of a cell is found to be $29$ volt and $28$ volt respectively when it delivers a current of $1$ ampere and $2$ ampere respectively. The emf and internal resistance of a cell are respectively

• A. 30V, 2$\Omega$
• B. 30V,1$\Omega$
• C. 29V, 1$\Omega$
• D. 28V,2$\Omega$

Answer 1

Answer: (B)

30V,1$\Omega$

$E-r=29$
$E-2r=28$
$\Rightarrow r=1\Omega$
$E=30V$