Physics Quiz: Magnetic Field and Electric Motors

What is a coil of many circular turns of insulated copper wire wrapped closely in the shape of a cylinder called?

• Capacitor

• Resistor

• Transformer

• Solenoid

What is the pattern of the magnetic field lines inside a current-carrying solenoid?

• Parallel straight lines

• Circular lines

• Radial lines

• Irregular lines

What is the magnet formed when a piece of soft iron is placed inside a solenoid?

• Electromagnet

• Permanent magnet

• Bar magnet

• Horseshoe magnet

Who suggested that the magnet must exert an equal and opposite force on the current-carrying conductor?

• Andre Marie Ampere

• James Clerk Maxwell

• Michael Faraday

• Nikola Tesla

What is the rule used to find the direction of the force on a current-carrying conductor in a magnetic field?

• Ohm's law

• Fleming's right-hand rule

• Fleming's left-hand rule

• Newton's first law

What device reverses the direction of flow of current through a circuit in an electric motor?

• Brush X

• Brush Y

• Split ring

• Axle O

What is used in commercial motors in place of a permanent magnet?

• Horseshoe magnet

• Bar magnet

• Neodymium magnet

• Electromagnet

What enhances the power of the motor in commercial motors?

• Aluminum core

• Copper core

• Soft iron core

• Steel core

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

• To hold the coil

• To rotate the axle

• To reverse the current

• To conduct electricity

What happens to the direction of force on the two arms of the coil when the current is reversed in an electric motor?

• The force reverses

• The force remains the same

• The force becomes zero

• The force increases