Question

Light from the sun allows a solar cell to move electrons from the positive to the negative terminal, doing $2.4\times {10}^{-19}J$of work per electron. What is the emf of this solar cell?

Short answer

The emf of the solar cell is$\mathbf{1}\mathbf{.}\mathbf{5}\mathbf{}\mathit{V}$

Step-by-step solution

Given information and theory used

Given :

Work per electron : $2.4\times {10}^{-19}J$

Theory used :

The work is equal to$W=q∆V$

Calculating the emf of the solar cell 

Writing $∆V\mathrm{as}\mathrm{emf},\epsilon$in our case, we have :

$\epsilon =\frac{W}{q}=\frac{2.4\times {10}^{-19}}{1.6\times {10}^{-19}}=\boxed{\mathbf{1}\mathbf{.}\mathbf{5}\mathbf{}\mathit{V}}$