The force on a charged particle moving in a magnetic field is given by:
$$ F = qvB $$
where $q$ is the charge, $v$ is the velocity, and $B$ is the magnetic field. First, we convert the kinetic energy to velocity, then calculate the force. Substituting the given values, we get the force acting on the proton to be $48 \times 10^{-12}$ N.