The correct answer is option 'c) Motor'. A motor is an electric device that works on the phenomenon of force on a current-carrying conductor in a magnetic field. Let's understand this in detail:

Force on a Current-Carrying Conductor:
When a current-carrying conductor is placed in a magnetic field, it experiences a force. This force is known as the Lorentz force and is given by the equation:
F = BIL sinθ
where F is the force, B is the magnetic field strength, I is the current flowing through the conductor, L is the length of the conductor, and θ is the angle between the direction of the current and the magnetic field.

Working Principle of a Motor:
A motor consists of a current-carrying coil or armature that is placed in a magnetic field. When an electric current is passed through the coil, it experiences a force according to the Lorentz force equation. This force causes the coil to rotate.

Mechanism of a Motor:
1. When an electric current is supplied to the motor, it flows through the armature coil, creating a magnetic field around it.
2. The armature coil is placed in a magnetic field produced by the permanent magnets or electromagnets in the motor.
3. According to the Lorentz force equation, the current-carrying coil experiences a force that is perpendicular to both the magnetic field and the direction of the current.
4. This force causes the armature coil to rotate, converting electrical energy into mechanical energy.
5. The rotation of the coil is used to drive the mechanical load attached to the motor, such as a fan, pump, or conveyor belt.

Applications of Motors:
Motors are used in various applications such as:
- Industrial machinery: Motors are used to power various machines in industries, including conveyor systems, pumps, and compressors.
- Electric vehicles: Motors are used in electric cars and bikes to drive the wheels.
- Household appliances: Motors are used in appliances like fans, refrigerators, washing machines, and air conditioners.
- Robotics: Motors are used in robotic systems to control the movement of robot arms and joints.
- Aerospace: Motors are used in aircraft and spacecraft for various functions, including controlling the movement of control surfaces and adjusting the position of satellites.

In conclusion, a motor is an electric device that utilizes the force on a current-carrying conductor in a magnetic field to convert electrical energy into mechanical energy. It finds wide applications in various industries and everyday life.