Magnetic force is a fundamental force of nature that causes magnetic materials to attract or repel each other. It is caused by the interaction between moving electric charges.
The magnetic force experienced by a charged particle is directly proportional to the strength of the magnetic field it is moving through. The direction of the force is perpendicular to both the direction of motion and the direction of the magnetic field.
The radius of a charged particle's trajectory is determined by the strength of the magnetic field and the speed of the particle. A stronger magnetic field or a higher speed will result in a larger radius of the trajectory.
The formula for calculating the magnetic force on a charged particle is F = qvBsinθ, where q is the charge of the particle, v is its velocity, B is the strength of the magnetic field, and θ is the angle between the velocity and the direction of the magnetic field.
The direction of the magnetic force can be determined using the right-hand rule. If the thumb of the right hand points in the direction of the particle's velocity and the fingers point in the direction of the magnetic field, then the palm will face in the direction of the magnetic force.