Question 1: Electric motors convert electrical energy into mechanical energy using the principle of magnetic forces acting on current-carrying conductors in a magnetic field.

Answer: Electric motors use magnetic forces on current-carrying conductors to produce rotational motion, converting electrical energy into mechanical energy.

Question 1: Name four main components of a simple electric motor.

Answer: Stator, rotor, commutator, brushes

Question 2: Explain briefly how magnetic forces cause the rotor to turn in an electric motor.

Answer: When current flows through the conductors in the magnetic field, Lorentz forces act on the conductors, creating a torque that causes the rotor to turn. The commutator reverses current direction to maintain continuous rotation.

Question 1: Describe the role of the magnetic field and current in producing force in an electric motor.

Answer: The magnetic field applies a force on the current-carrying conductors, and when current flows, it interacts with the magnetic field to produce a force (Lorentz force), resulting in motion.

Question 2: Multiple Choice: Which component reverses the direction of current in the motor to maintain continuous rotation?

Answer: Commutator

Question 1: Calculate the force acting on a conductor of length 0.5 meters carrying a current of 3 amperes in a magnetic field of 0.2 Tesla. Use the formula F = BIL sin θ, assuming θ = 90°.

Answer: F = 0.2 T × 3 A × 0.5 m × sin 90° = 0.3 N

Question 2: A motor's magnetic field strength is 0.15 Tesla, and the current in its coil is 5 A. If the length of the conductor in the magnetic field is 1 meter, what is the force acting on the conductor?

Answer: F = 0.15 T × 5 A × 1 m × sin 90° = 0.75 N

Question 1: Describe a common household device that uses an electric motor and explain how the motor's operation benefits the device.

Answer: A washing machine uses an electric motor to turn the drum, enabling clothes to be washed efficiently. The motor's ability to convert electrical energy into rotational motion makes it suitable for agitating and spinning clothes.

Question 2: Identify two safety precautions that should be followed when working with electric motors in a laboratory setting.

Answer: Ensure the motor is unplugged before maintenance and keep liquids away from electrical components.