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All magnetic fields are caused by

Two wires running parallel to each other experience

Two wires running perpendicular to each other experience

Two wires running anitparallel to each other experience

Einstein derived relativity from

The force on a moving charge in the presence of a magnetic field is always

The force on a moving charge in a magnetic field is always proportional to

The force on a moving charge parallel to a magnetic field is always

The force on a charge moving perpendicular to a magnetic field is given by

The force on a wire moving perpendicular to a magnetic field is given by

The force on a charge moving at some angle
*θ*
to a magnetic field is
proportional to

The total work done by a magnetic field on a moving charge is always

The net charge on a wire carrying a current
*I*
is

The magnetic force is always

All magnets have

A compass measures

The point on the compass of a needle near a current carrying wire always points

The magnetic field caused by a wire with current
*I*
is:

Magnetic field lines near straight wires are always

The force, per unit length, between two parallel current carrying wires is defined as

The unit of magnetic field, in CGS units, is

The magnitude of the magnetic field at a point
*P*
caused by a small length of
wire,
*dl*
, at an angle
*θ*
to the vector from
*dl*
to
*P*
is given by

What is the magnitude of the magnetic field of a wire carrying a current of
6×10^{10}
esu/sec, at a distance of 2 cm from the wire?

A ring of wire carrying a current creates what kind of magnetic field?

On the axis of a current carrying ring of radius
*b*
, at what point is the
magnetic field maximum?

A ring of radius 2 cm carries a current of
3×10^{10}
esu/sec. What is the
strength of the magnetic field at the center of the ring?

The field inside a long solenoid can be approximated as

The magnetic field inside a solenoid is maximum

A solenoid of length 1,000 cm has 2,000 turns carrying a current of
6×10^{10}
esu/sec. Because it is so long, it can be approximated near the center as an
infinite
solenoid. What is the magnetic field strength at the center of the solenoid?

A current carrying wire is placed along the axis of a long solenoid. In what direction does the force on the wire point?

The field along the axis of an infinitely long solenoid is given by

The first right hand rule is used to determine

The second right hand rule is used to determine

A ring and an infinite solenoid both have the same radius and current. Which one produces a stronger magnetic field on its axis?

The divergence of a vector field at a given point is

What is the divergence of the field
(2*x*, 2*y*, 2*x*)
?

What is the divergence of the field
(*x*
^{2}, *x* + *y*, *z*)
?

Gauss' theorem relates

Gauss' theorem only applies to

The curl of a vector field at a given point is

The curl measures

What is the curl of
(2*x*, 2*y*, 2*z*)
?

Stokes' Theorem relates

The line integral around any closed loop in an electric field is equal to

The line integral around any closed loop in a magnetic field is equal to

The curl of any magnetic field is

The divergence of any magnetic field is

The fact about the divergence in a magnetic field is due to

*Jda*
is equal to

How many licks does it take to get to the center of a tootsie roll pop?