Question

With what speed an $\alpha$ - particle should be projected towards $Cu$ nucleus such that it may be close to the nucleus ${10}^{-13}$m?

• A. $2.16\times {10}^6$ m/s
• B. $5.22\times {10}^6$ m/s
• C. $3.16\times {10}^6$ m/s
• D. $1.26\times {10}^6$ m/s

Answer 1

The correct option is C $3.16\times {10}^6$ m/s

from energy balanced

equation

$KE=PE$

$\frac{1}{\alpha }{m}_{\alpha }{V}^2=\frac{Kq,q_2}{r}$

$V=\sqrt{\frac{2K,q_{2}q}{rm\alpha }}$

$K=9\times {10}^9$

$q_1=$ particle

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

$q_2=CV=2\times 29\times 1.6\times {10}^{-19}$

$m\alpha =4\times 6.6\times {10}^{-27}$

$r={10}^{-13}$

$u=3.16\times {10}^6$m/sec