Magnetic Fields & Electromagnetism
A positive charge is moving with a velocity perpendicular to the position vector . According to the right-hand rule, what is the direction of the magnetic field at the location specified by ?
Parallel to the velocity .
In the same direction as the position vector .
Perpendicular to both and , determined by the right-hand rule.
Opposite to the direction of the velocity .
A particle with charge moves with a velocity of at a location from the origin. What is the magnitude of the magnetic field at a point where the angle between and is 90 degrees, given that and ?
9.0 x 10^{-12}
T
1.6 x 10^{-13}
T
1.6 x 10^{-11}
T
9.0 x 10^{-11}
T
Two identical positive charges are moving with the same speed . Charge 1 is located at (0, a, 0) and moving in the +x direction, and Charge 2 is located at (0, -a, 0) and moving in the +x direction. What is the direction of the net magnetic field at the origin (0, 0, 0)?
+z direction
-z direction
+y direction
The magnetic field is zero
A negative charge is moving to the right in a uniform magnetic field that points upwards. What is the direction of the magnetic force on the charge?
Upwards
Downwards
Into the page
Out of the page
An electron () moves with a velocity in a uniform magnetic field . Calculate the magnetic force vector acting on the electron.
9.6 \times 10^{-14} N \hat{k}
9.6 \times 10^{-14} N \hat{j}
A proton moves through a region with a spatially varying magnetic field given by . If the proton's velocity is , what is the magnetic force on the proton when it is located at (1, 1, 0)?
A charged particle moves with a constant velocity through a region where both electric and magnetic fields are present. If the electric and magnetic forces on the particle are in opposite directions, what can be said about the net force on the particle?
The net force is always zero.
The net force is the sum of the electric and magnetic forces.
The net force is the difference between the electric and magnetic forces.
The net force is the product of the electric and magnetic forces.

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A proton with a charge of 1.6 \times 10^{-19} C
moves with a velocity of in a region with an electric field and a magnetic field . Calculate the net force vector on the proton.
An electron moves through perpendicular electric and magnetic fields. The electric field is 100 V/m
and the magnetic field is 0.5 T
. What velocity must the electron have to pass through undeflected?
50 m/s
200 m/s
0.005 m/s
0.02 m/s
In the Hall effect, a magnetic field is applied perpendicular to a current-carrying conductor. What is the primary result of this effect?
An increase in the conductor's temperature.
A change in the conductor's resistance.
A voltage difference is created across the conductor, perpendicular to both the current and the magnetic field.
The conductor becomes magnetized.