The radius of curvature of the path of a charged particle in a uniform magnetic field is directly proportional to the

momentum of the particle

The correct answer is Option (2) → momentum of the particle

The radius of curvature of a charged particle moving perpendicular to a uniform magnetic field is given by:

$r = \frac{mv}{qB}$

Here, $m$ is mass, $v$ is velocity, $q$ is charge, and $B$ is magnetic flux density.

Momentum of the particle: $p = mv$

Therefore, $r = \frac{p}{qB}$

Hence, the radius of curvature is directly proportional to the momentum of the particle.

Answer: momentum of the particle