Question

Consider the following statements,
$A$. Magnitudes and direction of deflection of $alpha$ and $beta$ rays are different while passing through the same intensity magnetic field.
$B$. Beta-plus rays have all the properties of beta rays except that it is made of positive charge.

• A. Only statement $A$ is correct
• B. Only statement $B$ is correct
• C. Both statements are correct
• D. None of the above

Answer 1

The correct option is C Both statements are correct

Magnetic force acting on a charged particle $\overrightarrow{F}=q(\overrightarrow{v}\times \overrightarrow{B})$

Charges of alpha and beta rays are different and are of opposite signs. Thus magnetic force acting on both the particles is different and in opposite direction. Hence alpha and beta rays get deflected by unequal amount as well as in opposite direction.

Hence statement A is correct.

Beta rays consist of electrons, thus beta rays have all the properties of electrons. Whereas beta-plus rays consist of positron, these rays have all the properties of positron. But electron and positron have all the properties same except that the electron has negative charge while positron has positive charge of equal amount. Hence beta-plus rays have all the properties of beta rays except that it is made up of positive charge. So, statement B is also correct.