MCQs

Q481: Metals are good conductors of electricity because they have free _____?

• A) Electrons
• B) Protons
• C) Neutrons

Q482: The turn ratios of a transformer is 10. It means ______?

• A) Is = 10 Ip
• B) Np - 10Ns
• C) Ns = 10 Np

Q483: The step-up transformer ______?

• A) Increases the input current
• B) Increases the input voltage
• C) Has more turns in the primary

Q484: The direction of induced e.m.f. in a circuit is in accordance with conservation of _____?

• A) Mass
• B) Charge
• C) Energy

Q485: Which part of a D.C motor reverses the direction of current through the coil every half-cycle?

• A) The armature
• B) The commutator
• C) The brushes

Q486: D.C motor converts _______?

• A) Mechanical energy into electrical energy
• B) Mechanical energy into chemical energy
• C) Electrical energy into mechanical energy

Q487: f the current in a wire which is placed perpendicular to a magnetic field increases, the force on the wire ______?

• A) Increases
• B) Decreases
• C) Remains the same

Q488: The presence of a magnetic field can be detected by _______?

• A) Small mass
• B) Stationary positive charge
• C) Magnetic compass

Q489: What is the direction of the magnetic field lines inside a bar magnet?

• A) From north pole to south pole
• B) South pole to north pole
• C) From side to side

Q490: Which statement is true about the magnetic poles?

• A) Unlike poles repel
• B) Like poles attract
• C) A single magnetic pole does not exist