Electric Motor: How Current and Magnetic Fields Cause Rotation

The video tutorial explains the motor effect, where a current-carrying conductor in a magnetic field experiences a force, leading to rotation. It details how electric motors use this effect, describing the role of magnetic fields, conducting rings, and split rings in motor operation. Fleming's left hand rule is used to determine force direction, ensuring continuous rotation.

What is the motor effect?

• A wire generates electricity when placed in a magnetic field.

• A conductor rotates without any external force.

• A magnetic field is created by a stationary wire.

• A current-carrying wire in a magnetic field experiences a force.

How can the direction of force on a conductor be determined?

• Using the right-hand rule

• Using Fleming's left-hand rule

• By measuring the current

• By observing the magnetic field lines

What role do brush contacts play in an electric motor?

• They connect the conducting ring to an external current source.

• They stop the motor from rotating.

• They generate the magnetic field.

• They reverse the direction of the magnetic field.

In which direction does the force act on the left side of the conducting ring?

• To the right

• Upwards

• To the left

• Downwards

What is the purpose of the split ring in an electric motor?

• To stop the motor from rotating

• To change the direction of current every half turn

• To increase the speed of rotation

• To decrease the magnetic field strength

How does the split ring affect the current in arm A after a half turn?

• The current flows into the screen.

• The current stops flowing.

• The current flows in a circular path.

• The current flows out of the screen.

What ensures the continuous clockwise rotation of the conducting ring?

• The decrease in magnetic field strength

• The split ring changing current direction

• The increase in current strength

• The constant magnetic field