phys 250 exam 3
conceptual/objective questions
& answers
Current in a circuit containing a coil, a resistor, and a battery
reached constant value.
1. Does coil have inductance?
2. Does it affect value of current? - answer 1. Yes. Inductance
exists regardless of current
2. No
Rectangular conducting loop place near a long wire carrying a
current I - answer The current is clockwise
Flat coil of wire is placed in uniform magnetic field. Magnetic flux
is through the coil is a max if the plane of the coil is - answer xz
plane
A square, flat loop of wire is pulled at constant velocity through a
region of uniform magnetic field directed perpendicular to the
plane of the loop - answer no current is induced, charge
seperation occurs, with top edge positive
Can an object exert a force on itself? - answer No
, A bar moves on rails to the right with a velocity v and a uniform
constant magentic field is directed out of the range - answer
Current is clockwise, an external force is required
When a coil induces emf in itself, does it exert a force on itself? -
answer No
What happens to the amplitude of the induced emf when the rate
of rotation of a generator coil is doubled? - answer It becomes 2x
larger
Oscillator is ____ if
1. overdamped
2. underdamped - answer 1. R > Rc
2. R < Rc
Coil of wire in space has small current, with no battery and no
magnets. What causes the current - answer Traveling through
magnetic field of earth
Inductive reactance ____ when frequency doubles - answer
doubles
How does a hydroelectric dam make power - answer Spins rotor
and generates magnetic field and induced emf
conceptual/objective questions
& answers
Current in a circuit containing a coil, a resistor, and a battery
reached constant value.
1. Does coil have inductance?
2. Does it affect value of current? - answer 1. Yes. Inductance
exists regardless of current
2. No
Rectangular conducting loop place near a long wire carrying a
current I - answer The current is clockwise
Flat coil of wire is placed in uniform magnetic field. Magnetic flux
is through the coil is a max if the plane of the coil is - answer xz
plane
A square, flat loop of wire is pulled at constant velocity through a
region of uniform magnetic field directed perpendicular to the
plane of the loop - answer no current is induced, charge
seperation occurs, with top edge positive
Can an object exert a force on itself? - answer No
, A bar moves on rails to the right with a velocity v and a uniform
constant magentic field is directed out of the range - answer
Current is clockwise, an external force is required
When a coil induces emf in itself, does it exert a force on itself? -
answer No
What happens to the amplitude of the induced emf when the rate
of rotation of a generator coil is doubled? - answer It becomes 2x
larger
Oscillator is ____ if
1. overdamped
2. underdamped - answer 1. R > Rc
2. R < Rc
Coil of wire in space has small current, with no battery and no
magnets. What causes the current - answer Traveling through
magnetic field of earth
Inductive reactance ____ when frequency doubles - answer
doubles
How does a hydroelectric dam make power - answer Spins rotor
and generates magnetic field and induced emf
