Torque on a current carrying loop.

When the coil is part of a d.c. motor, what must be connected directly to X and Y?

• d.c. supply

• slip rings

• soft-iron core

• split-ring commutator

A wire hangs between the poles of a magnet.
When there is a current in the wire, in which direction does the wire move?

• A
• B
• C
• D

The diagram shows a beam of electrons entering a magnetic field. 
What is the effect of the magnetic field on the electrons? 

• They are deflected into the plane of the diagram. 
• They are deflected out of the plane of the diagram.
• They are deflected towards the bottom of the diagram. 
• They are deflected towards the top of the diagram. 

Which of the following has no effect on the size of the turning effect on the coil of an electric motor?

• the size of the current in the coil
  
• the direction of the current in the coil
  
• the number of turns in the coil
  
• the strength of the magnetic field
  

What angle must there be between a magnetic field and a conductor in order for the maximum force to be exerted?

• 180

• 45

• 90

• 270

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5

Name one factor that does not affect the size of a force in on a current-carrying conductor placed in a magnetic field?

• Gravity

• Magnetic flux density/size of magnetic field

• Size of the current

• Length of the conductor

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5

Give two ways you can reverse the direction of a basic dc motor?

• Reverse the current

• Keep the current the same

• Reverse the magnetic field

• Keep the magnetic field the same

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5