In which direction will be the force on an electron moving in a magnetic the largest?
The same as the magnetic field direction.
Exactly opposite to the magnetic field direction.
Perpendicular to the magnetic field direction.
At an angle other than 90° to the magnetic field direction.
An electron moving in a uniform magnetic field of induction of intensity B, has its radius directly proportional to
its charge
magnetic field
speed d. none of these
none of these
The induced voltage across a stationary conductor in a stationary magnetic field is
zero
reversed in polarity
increased
decreased
The induced voltage across a coil with 250 turns that is located in a magnetic field that is changing at a rate of 8 Wb/s is
1000V
2000 V
31.25V
3125V
All pieces of iron have magnetic domains, why are most iron nails not magnetic?
they cannot conduct electricity
their domains are all oriented with respect to magnetic poles
their domains are randomly oriented, canceling out most magnetic forces
their atoms contain 4 electrons that spin magnetism is un-cancelled
Which is not a material that is commonly used to make a magnet?
iron
cobalt
nickel
copper
Why are most materials not magnetic?
they do not conduct electricity
they are not metals
the magnetic fields produced by the electron spin is canceled
they are insulators, meaning that electrons are not free to move around in the atomic lattice
The ability of a material to remain magnetized after removal of the magnetizing force is known as
permeability
reluctance
hysteresis
retentivity
Magnet A has twice the magnetic field strength of magnet B, and at a certain distance pulls on the magnet B with a force of 100 N. What is the amount of force that magnet A exerts on magnet B ?
at or about 50 N
exactly 100 N
exactly 150N
More information is needed
In rare earth magnets, such as gadolinium or neodymium what is the main contributor to the magnetic field?
electron spin
electron orbital motion
proton spin
Proton orbital motion
