If uncertainty in position and momentum are equal, then uncertainty in velocity is:

1.  $\frac{1}{2\mathrm{m}}\sqrt{\frac{\mathrm{h}}{\mathrm{\pi }}}$

2.  $\sqrt{\frac{\mathrm{h}}{2\mathrm{\pi }}}$

3.  $\frac{1}{\mathrm{m}}\sqrt{\frac{\mathrm{h}}{\mathrm{\pi }}}$

4.  $\sqrt{\frac{\mathrm{h}}{\mathrm{\pi }}}$

If the mass of electron is 9.11×10^-31 kg  and the planck's constant is 6.626 ×10^-34 Js, then the uncertainty involved in the measurement of velocity within a distance of 0.1Å is :

1. $5.79\times {10}^6 m{s}^{-1}$

2. $5.79\times {10}^7 m{s}^{-1}$

3. $5.79\times {10}^8 m{s}^{-1}$

4. $5.79\times {10}^5 m{s}^{-1}$

Uncertainity in position of a $e^{-}$ and He is similar. If uncertainity in momentum of $e^{-}$is  $32\times {10}^5$ , then uncertainity in momentum of He will be :

1. $32 \times {10}^5$

2. $16 \times {10}^5$

3. $8 \times {10}^5$

4. None of the above