A deuteron and an alpha particle having same momentum are in turn allowed to pass through a magnetic field B, acting normal to the direction of motion of the particles. Calculate the ratio of the radii of the circular paths described by them.

Explanation

To solve the problem of finding the ratio of the radii of the circular paths described by a deuteron and an alpha particle in a magnetic field, we can follow these steps:

### Step 1: Understand the relationship between radius, momentum, and magnetic field
When a charged particle moves in a magnetic field, it experiences a magnetic force that acts as the centripetal force required for circular motion. The radius \( r \) of the circular path is given by the formula:

\[ r = \frac{mv}{qB} \]
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