Slide 1 / 25
1 A particle of charge +q enters a uniform magnetic field B directed
into the page. The direction of the magnetic force FB on the particle
is
A top of the page
B bottom of the page
C Left
D Right
E out of the page
Slide 2 / 25
2 A particle of charge -q enters a uniform magnetic field B directed
out of the page. The direction of the magnetic force FB on the
particle is
A top of the page
B bottom of the page
C Left
D Right
E out of the page
Slide 3 / 25
3 A particle of charge -q enters a uniform magnetic field B directed
out of the page. The direction of the magnetic force FB on the
particle is
A top of the page
B bottom of the page
C Left
D Right
E no force applied
Slide 4 / 25
4 A charge particle -q enters a uniform magnetic field B. If FB is the
magnetic force, which of the following represents the particle's
velocity?
A qB/FB
B q/FBB
C FB/qB
D 1/qFBB
E B/qFB
Slide 5 / 25
5 A current carrying wire carries a current into the page. The wire is
placed in a uniform magnetic field directed to the right. The
magnetic force on the current is directed
A top of the page
B bottom of the page
C left
D right
E into the page
Slide 6 / 25
6 A current carrying wire of length L and mass m is placed in a
uniform magnetic field B. The current in the wire is I. What must
the direction of the field be in order to balance the gravity?
A into the page
B bottom of the page
C right
D left
E out of the page
Slide 7 / 25
7 A current carrying wire of length L and mass m is placed in a
uniform magnetic field. The current in the wire is I. What must the
magnitude of the field be in order to balance the gravity?
A mg/IL
B mL/Ig
C Ig/gL
D Ig/mL
E Il/mg
Slide 8 / 25
8 A positive charges travels through a uniform magnetic field. The
diagram represents the direction of the particle’s velocity and
magnetic force on it at the certain point. What is the direction of the
magnetic field B?
A out of the page
B into the page
C right
D left
E top of the page
Slide 9 / 25
Slide 10 / 25
10 A negatively charged particle of charge q and mass m moves with
constant speed v in a circular path in the presence of a uniform
field B. Which of following represents the radius r of the moving
charge?
A qB/mv
B qv/mB
C mB/qv
D qBm/v
E mv/qB
Slide 11 / 25
11 An electron enters a region where both a magnetic field B into the
page and electric field E between the two plates act on the particle
as shown below. What must be the direction of the electric field in
order for the particle to move in the straight line?
A top of the page
B bottom of the page
C Left
D Right
E into the page
Slide 12 / 25
12 An electron enters a region where both a magnetic field B into the
page and electric field E between the two plates act on the particle
as shown above. Which of the following represents the particle’s
velocity when it passes through the region of two fields
undeflected?
A E/B
B B/E
C B2/E
D B/
E E2/B
Slide 13 / 25
13 An electron enters a region where both a magnetic field B into the
page and electric field E between the two plates act on the particle
as shown above. If the electric field is removed which of the
following represents the motion of the electron?
A To the right
B Parabolic path downward
C Parabolic path upward
D Circular path clockwise
E Circular path counter clockwise
Slide 14 / 25
14 An electric current flows in a closed loop made of two fixed rails,
power supply, and very light rod that is free to move on the top of
the rails. A uniform magnetic field is perpendicular to the plane of
the circuit. What is the direction of magnetic force on the rod?
A +y
B -y
C -x
D +x
E +z
Slide 15 / 25
15 An electric current flows in a closed loop made of two fixed rails,
power supply, and very light rod of length L that is free to move on
the top of the rails. A uniform magnetic field B is perpendicular to
the plane of the circuit. If current source supplies voltage V and net
resistance R, what is the magnitude of the magnetic force on the
rod?
A VBL/R
B VB/RL
C BL/VR
D VL/BR
E VR/BL
Slide 16 / 25
16 A rectangular piece of metal is placed in a uniform magnetic field
and connected to a battery on two opposite sides. Which one of
the following statements is incorrect?
A The conventional current in the
metal plate is directed from the left
to the right
B The flow of electrons passes the metal
plate from the right to the left
C Point L has higher potential than point N
D Point N has higher potential that point L
E The potential difference between point L and N is
explained by Hall Effect
Slide 17 / 25
17 An electric current flows straight up. An electron approaches the
current from East. What is the direction of the magnetic force on
the electron due to the current?
A East
B West
C North
D South
E Up
Slide 18 / 25
18 A positively charged particle moves in the region of an electric
current placed below the particle. What is the direction of magnetic
force on the charge?
A Top of the page
B Bottom of the page
C Left
D Right
E Out of the page
Slide 19 / 25
19 A uniform magnetic field B is parallel to the xy-plane and in the +y-direction, as
shown above. A positively charged particle initially moves with velocity v in the
xy-plane at an angle Ɵ to the magnetic field and the y-axis. Which of the
following paths will the particle follow in the presence of the magnetic field?
A Continue a straight-line path
B A circular path in the xy-plane
C A circular path in the yz-plane
D A helical path with its axis parallel to the y-axis
E A helical path with its axis parallel to the z-axis
Slide 20 / 25
20 A uniform magnetic field B is parallel to the xy-plane and in the +ydirection, as shown above. A positively charged particle q initially
moves with velocity v in the xy-plane at an angle Ɵ to the magnetic
field and the y-axis. What is the magnitude of the force acting on
the charge?
A qvB
B qvB cosƟ
C qvB sinƟ
D qv/BsinƟ
E qvB tanƟ
Slide 21 / 25
21 A proton moves parallel to the x-axis in the positive x-direction.
What must the direction of the electric field be in order to keep the
proton going undeflected if the magnetic field is established in +y
direction?
A Positive y-direction
B Postitive z-direction
C Negative x-direction
D Negative y-direction
E Negative z-direction
Slide 22 / 25
22 A current-carrying loop of wire is placed in a uniform magnetic field
perpendicular to the plane of the loop. Under the influence of the
magnetic force the loop will
A rotate with respect to its center
B rotate with respect to its diameter
C contract
D expand
E stays stationary
Slide 23 / 25
23 A bar magnet and a wire loop carrying current I are arranged as
shown below. What is the direction of the force on the current loop
due to the magnet?
A Toward the magnet
B Away from the magnet
C Toward the top of the page
D Toward the bottom of the page
E There is no force on the current loop
Slide 24 / 25
24 A charged particle in a uniform magnetic field B moves in a circular
path of radius r. Which of the following represents the frequency of
revolution f?
A qB/2πm
B qm/2πB
C 2πB/qm
D qBm/2π
E qm/2πB
Slide 25 / 25
25 A loop of wire has a current I running through it in a counter
clockwise direction. An electron moving with velocity v downward is
placed outside of the loop and in the plane of the loop. Which of
the following represents the direction of the magnetic force due to
the loop on the electron?
A To the right
B To the left
C Into the page
D Out of the page
E To the top of the page