Question

Three ions $H^{+},H{e}^{+}$ and $O^{+2}$ having same kinetic energy pass through a region in which there is a unit magnetic field perpendicular to their velocity, then.

• A. $H^{+}$ will be least deflected
• B. $H{e}^{+}$ and $O^{+2}$ will be deflected equally
• C. $O^{+2}$ will be deflected most
• D. All will be deflected equally

Answer 1

The correct option is B $H{e}^{+}$ and $O^{+2}$ will be deflected equally

$R=\frac{\surd (2\times m\times K)}{Bq}$

radius B=magnetic field intensity q = charge K = kinetic energy

In this case $K,B,2$ are constant

r {proportional to} (√m)/qr

$H^{+}:H{e}^{+}:O^{++}$ $=\left(\surd 1\right)/1e:\left(\surd 4\right)/1e:\left(\surd 16\right)/2e$[e is charge of electron ]r

$H^{+}:H{e}^{+}:O^{++}=1:2:2$

Hence $H{e}^{+}$ and $O^{++}$ will deviate by same amount and more than $H^{+}$