PHYS 6B Lecture Notes - Lecture 13: Right-Hand Rule, Electric Field, Net Force

Which one of the following statements best explains why a constantmagnetic field can do no work on a moving charged particle?
a)The magnetic field is conservative.
b)The magnetic force is a velocity dependent force.
c)The magnetic field is a vector and work is a scalarquantity.
d)The magnetic force is always perpendicular to the velocity of theparticle.
e)The electric field associated with the particle cancels theeffect of the magnetic field on the particle.

1 - A compass in a magnetic field will line up __________.

(A) - with the north pole pointing perpendicular to the magnetic field

(B) - with the north pole pointing opposite the direction of the magnetic field

(C) - with the north pole pointing in the direction of the magnetic field

2 - The magnetic field lines due to a straight, current-carrying wire are __________.

(A) - straight lines parallel to the wire

(B) - circles around the wire

(C) - straight lines perpendicular to the wire

3 - Two parallel wires carry a current in the same direction. There is ___________ between the wires.

(A) - a repulsive force

(B) - no force

(C) - an attractive force

4 - The direction of the magnetic force on a moving charged particle in a magnetic field is __________.

(A) - both perpendicular to the velocity and perpendicular to the magnetic field

(B) - perpendicular to the magnetic field

(C) - perpendicular to the velocity

Three points are located in a uniform magnetic field as shown. The B field points into the screen.

(1) A positively charged particle is located at point A and is stationary. The direction of the magnetic force on the particle is

right

left

into the screen

out of the screen

Zero

(2) The positive charge moves from point A toward B. The direction of the magnetic force on the particle is:

right

left

into the screen

out of the screen

Zero