Final answer:
The magnetic force acting on a moving charge is given by F = qvB sin θ, and for a wire carrying current in a magnetic field, it is F = I l B sin θ. The direction follows the Right Hand Rule-1 (RHR-1).
Step-by-step explanation:
The equation for magnetic force acting on a moving charge is F = qvB sin θ, where F is the force, q is the charge, v is the velocity of the charge, B is the magnetic field strength, and θ is the angle between the velocity and the magnetic field. The direction of the force follows the Right Hand Rule-1 (RHR-1), where the thumb represents the charge's velocity (if positive), the fingers the direction of the magnetic field, and the perpendicular palm denotes the direction of the force.
For a straight wire carrying a current I, the equation for magnetic force is F = I l B sin θ, where l is the length of the wire within the magnetic field. If the wire is in a uniform magnetic field and the current is perpendicular to the field (θ is 90 degrees), the equation simplifies to F = I l B.