Final answer:
The magnetic force experienced by a current-carrying wire in a magnetic field increases with the length of wire because the force is directly proportional to this length. The force is given by the equation F = IIB sin θ, and its direction can be found with the right-hand rule.
Step-by-step explanation:
The magnetic force experienced by a length of wire carrying a current in a magnetic field is described by the equation F = IIB sin θ, where F is the force, I is the current, B is the magnetic field, l is the length of wire within the magnetic field, and θ is the angle between the wire and the direction of the magnetic field.
According to this equation, the magnetic force is directly proportional to the length of the wire—the longer the wire within the field, the greater the force. This is significant because it highlights that a large magnetic field can create a significant force even on a relatively small length of wire. Additionally, it is worth noting that the force is maximized when the angle θ is 90 degrees, as sin θ becomes 1, simplifying the expression to F = IBl. The direction of the force can be determined using the right-hand rule (RHR-1), where you point your thumb in the direction of the current and your fingers in the direction of the magnetic field; then a perpendicular to your palm indicates the direction of the force.