When a loop of current-carrying wire turns continuously in a magnetic field, a _ is created.?
The Correct Answer and Explanation is :
When a loop of current-carrying wire turns continuously in a magnetic field, an electromagnetic torque is created. This phenomenon is fundamental to the operation of electric motors and generators.
Explanation:
When a current flows through a wire, it generates a magnetic field around it due to Ampère’s law. If this wire is shaped into a loop and placed within an external magnetic field, several interactions occur. The magnetic field exerts a force on the current-carrying loop according to the Lorentz force law, which states that a magnetic field exerts a force on a moving charge.
As the loop turns in the magnetic field, the direction of the current and the orientation of the magnetic field create a situation where different sides of the loop experience different forces. This differential force generates a torque around the loop’s axis of rotation. The torque is proportional to the product of the current flowing through the loop, the length of the wire in the magnetic field, the strength of the magnetic field, and the sine of the angle between the magnetic field and the normal to the loop’s surface. Mathematically, the torque (( \tau )) can be expressed as:
[
\tau = n \cdot I \cdot A \cdot B \cdot \sin(\theta)
]
Where:
- ( n ) is the number of loops,
- ( I ) is the current,
- ( A ) is the area of the loop,
- ( B ) is the magnetic field strength,
- ( \theta ) is the angle between the magnetic field and the loop’s normal.
As the loop rotates, the torque keeps it in continuous motion, converting electrical energy into mechanical energy. This principle is used in various applications, such as electric motors, where the rotational movement can perform useful work, and generators, where mechanical energy is converted back into electrical energy. The continuous turning of the loop in a magnetic field enables the persistent conversion between electrical and mechanical energy, which is crucial for the functioning of numerous electrical devices in our daily lives.