Module 5 quiz
a magnet attracts
some substances and repels others
Direct electric current cannot be used to operate
transformers
When an observer moves past a stationary electric charge, she detects
both an electric and a magnetic field
The conventional unit of battery capacity is the ampere-hour, which is actually a unit of
electric charge
A kilowatt hour is a unit of
energy
The current with which a transformer is used
must be ac
When the voltage across a certain resistance is V, the power delivered is P. If the voltage is halved to V/2, the power delivered becomes
p/4
A molecule that has lost an electron becomes a
positive ion
A volt is a unit of electric:
potential difference
Which of the following statements is not true?
protons and electrons have equal masses
A current-carrying wire is in a magnetic field with the direction of the current parallel to that of the field.
the wire has no tendency to move or to turn
a current-carrying wire is in a magnetic field with the direction of the current perpendicular to that of the field
the wire tends to move perpendicular to the field
Relative to the electric force between two protons, the gravitational force between them is
weaker
Ohm's law
holds only for metals
Three 12-V batteries cannot be connected to give a voltage for the set of
6V
which of the following statements is not true?
a proton in an atom circulates around its nucleus
the electrons in an atom
are some distance away from the nucleus
When a current passes through a resistance, the electric energy that is lost
becomes heat
A negative electric charge
interacts with both positive and negative charges
A compass needle tends to
line up parallel to a magnetic field