Question Set #13
When the world one day runs out of oil, we will not be able to produce electricity anymore
False
The field(s) surrounding every stationary neutron is(are)
None of these
Which of the following materials contain billions of electrons in motion that are surrounded by tiny magnetic fields?
All four of these
The field(s) surrounding every moving proton is(are)
Always both electric and magnetic
Break a magnet in two and you
Always produce two magnets, each with north and south poles, no matter what the size of the original magnet.
An electric motor is very similar to
An electric generator
Like kinds of magnetic poles repel while unlike kinds of magnetic poles
Attract
Magnetism is due to the motion of electrons as they
Choices a and b are both correct (move around the nucleus and spin on their axes)
A device that transforms mechanical energy into electrical energy is a
Generator
Which scientist is credited for inventing the first electric motor?
Michael Faraday
The source of all magnetism is
Moving electric charge
The field(s) surrounding every moving neutron is(are)
None of these
Several paper clips dangle in a chain from the north pole of a magnet. The induced pole in the bottom of the lowermost paper clip is a
North pole
If a magnet is pushed into a coil, voltage is induced across the coil. If the same magnet is pushed into a coil at half the speed
One half as much voltage is induced
If a magnet is pushed into a coil, voltage is induced across the coil. If the same magnet is pushed into a coil with half the number of loops,
One half as much voltage is induced
Electromagnets may be made stronger by
Only a and b
An electromagnet is made by wrapping insulated wire around a steel nail and connecting the wire ends to a dry cell battery. If you want this electromagnet to reverse its north and south poles, then you should
Reverse the current flow OR wrap the nail in the opposite way, but don't do both
The reason a magnet will not pick up an unmagnetized plastic paper clip is that
The magnet cannot temporarily magnetize the plastic paper clip
The reason a magnet can pick up an unmagnetized steel paper clip is tha
The magnet temporarily magnetizes the paper clip
When a magnet is plunged in and out of a closed coil of wire, voltage is induced in the coil. If the rate of the in-and-out motion is tripled, the induced voltage is
Tripled
DC motors are fairly simple and inexpensive to make
True
If a magnet is pushed into a coil, voltage is induced across the coil. If the same magnet is pushed into a coil at twice the speed
Twice as much voltage is induced
An iron nail is more strongly attracted to the
north or south pole - no difference really
