A proton has a mass of 1.67 × 10-27 kg and charge 1.6 × 10-19 coulomb. If the proton is to be accelerated through a potential difference of one million volt, then the KE is

Q:    A proton has a mass of 1.67 × 10-27 kg and charge 1.6 × 10-19 coulomb. If the proton is to be accelerated through a potential difference of one million volt, then the KE is

(a) 1.6 × 10-15 J

(b) 1.6 × 10-13 J

(c) 1.6 × 10-25 J

(d) 3.2 × 10-13 J

Ans: (b)

Sol: $\large KE = \frac{1}{2} m v^2 = e V$

$\large KE = 1.6 \times 10^{-19} \times 10^6$

= 1.6 × 10-13 J