Question

How much work would be required to move a proton from the negative to the positive plate?

• A. $-3.6\times {10}^{-18}J$
• B. $3.6\times {10}^{-19}J$
• C. $3.6\times {10}^{-18}J$
• D. $-3.6\times {10}^{-19}J$

Answer 1

The correct option is C $3.6\times {10}^{-18}J$

Given two plates $1.5cm$ apart i.e, $d=1.5cm$

Electric field, $E=1500N/C$

We have to find the work required to move a proton from one plate to another i.e, from negative to positive plate.

Since the proton (charge $=1.6\times {10}^{-19}$) is moved from negative to positive plate, work done is positive and equal to $W$.

$W=q\times$ change in potential

$=q\times \Delta V$

As, $\Delta V=E\times d$

So, $W=q\times E\times d$

Substituting the values, we get

$W=1.6\times {10}^{-19}\times 1500\times 1.5\times {10}^{-2}$

$360\times {10}^{-20}$

$=3.6\times {10}^{-18}J$