Question 1: Define Fleming's Left Hand Rule and explain its purpose in physics.

Answer: Fleming's Left Hand Rule is a mnemonic used to determine the direction of force on a current-carrying conductor in a magnetic field. It helps predict the movement of the conductor in a motor effect.

Question 2: List the three directions involved in Fleming's Left Hand Rule and their corresponding physical quantities.

Answer: The three directions are: the direction of the Magnetic Field (B), the Current (I), and the Force (F).

Question 3: Describe how the magnetic field interacts with the current in a conductor to produce motion.

Answer: The magnetic field exerts a force on the moving charges in the conductor due to the Lorentz force, resulting in a force on the conductor that causes motion.

Question 1: A straight wire of length 0.5 meters carries a current of 3 amperes in a magnetic field of 0.2 tesla. Calculate the force acting on the wire. (Use F = BIL sin θ, assume θ = 90°)

Answer: F = 0.2 T × 0.5 m × 3 A × sin 90° = 0.2 × 0.5 × 3 × 1 = 0.3 newtons

Question 2: If a force of 2.4 N acts on a conductor of length 0.6 m in a magnetic field of 0.4 T, what is the current flowing through the conductor? (Use I = F / (B × L × sin θ), assume θ = 90°)

Answer: I = 2.4 N / (0.4 T × 0.6 m × 1) = 2.4 / 0.24 = 10 amperes

Question 1: Describe a simple experiment to demonstrate Fleming's Left Hand Rule, including the key variables involved.

Answer: Use a straight wire placed in a magnetic field with a power supply to pass current. The direction of force can be observed by the movement of the wire. Variables include magnetic field strength, current, and length of the wire.

Question 2: List two safety precautions necessary when conducting experiments involving electric currents and magnetic fields.

Answer: Ensure the circuit is switched off before adjusting components; avoid contact with live wires to prevent electric shocks.

Question 1: A conducting rod of length 0.3 meters moves at a velocity of 5 m/s perpendicular to a magnetic field of 0.1 T. Calculate the induced emf across the rod.

Answer: E = B × L × v = 0.1 T × 0.3 m × 5 m/s = 0.15 volts

Question 2: Explain how increasing the magnetic field strength affects the force on a current-carrying conductor in a motor.

Answer: Increasing the magnetic field strength increases the force exerted on the conductor, as force is directly proportional to magnetic flux density (B).

Question 1: A motor armature experiences a force of 0.5 N when a current of 2 A flows through a 0.4 m length of wire in a magnetic field. What is the magnetic flux density B? (Use F = BIL sin θ, θ = 90°)

Answer: B = F / (I × L × sin 90°) = 0.5 / (2 × 0.4 × 1) = 0.5 / 0.8 = 0.625 tesla

Question 2: In a certain experiment, the magnetic field is directed east, the current flows north, and the force is upwards. Use Fleming's Left Hand Rule to verify if these directions are consistent.

Answer: Yes, they are consistent.

Question 3: Explain how Fleming's Left Hand Rule can be applied to determine the direction of force in an electric motor's coil.

Answer: Fleming's Left Hand Rule states that if you align your left hand so that the First finger points in the direction of the magnetic Field (from North to South), the Second finger in the direction of the Current (conventional current from positive to negative), then the Thumb will point in the direction of the Force (motion). This helps in predicting the movement of the coil in the motor based on the directions of magnetic field and current.