Is it possible to orient a current loop in a uniform magnetic field such that the loop will not tend to rotate?
Yes, it is possible to orient a current loop in a uniform magnetic field such that the loop will not tend to rotate. This can be achieved by aligning the plane of the loop parallel to the magnetic field.
To understand why this orientation prevents rotation, we need to consider the interaction between the magnetic field and the current carrying loop. When a current flows through a wire, it generates a magnetic field around it. This magnetic field interacts with the external magnetic field, resulting in a torque on the loop.
The torque acting on a current loop in a magnetic field can be calculated using the equation:
τ = NIABsinθ
where τ represents the torque, N is the number of turns in the loop, I is the current flowing through the loop, A is the area enclosed by the loop, B is the magnetic field strength, and θ is the angle between the normal to the loop and the direction of the magnetic field.
To prevent the loop from rotating, the torque should be zero. This means that either the angle θ should be zero (θ = 0°) or the area of the loop should be zero. In the case of a current loop, the area cannot be zero, so we choose θ to be zero.
By aligning the plane of the loop parallel to the magnetic field, the angle θ becomes zero, resulting in a torque of zero. This prevents the loop from rotating.
In summary, to orient a current loop in a uniform magnetic field such that the loop does not tend to rotate, align the plane of the loop parallel to the magnetic field.