Transcript FGT3_ConcepTestsch28 quiz

ConcepTest PowerPoints
Chapter 28
Physics for Scientists and
Engineers, 3rd edition
© 2005 Pearson Prentice Hall
Fishbane
Gasiorowicz
Thornton
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ConcepTest 28.1a Magnetic Force I
A positive charge enters a
uniform magnetic field as
shown. What is the direction
of the magnetic force?
1) out of the page
2) into the page
3) downwards
4) to the right
5) to the left
x x x x x x
v
x x x x x x
x x x xq x x
ConcepTest 28.1b Magnetic Force II
A positive charge enters a
uniform magnetic field as
shown. What is the direction
of the magnetic force?
1) out of the page
2) into the page
3) downwards
4) upwards
5) to the left
x x x x x x
x x x x vx x
q
x x x x x x
ConcepTest 28.1c Magnetic Force III
A positive charge enters a
uniform magnetic field as
shown. What is the direction
of the magnetic force?
1) out of the page
2) into the page
3) zero
4) to the right
5) to the left


v

q

ConcepTest 28.1d Magnetic Force IV
1) out of the page
A positive charge enters a
uniform magnetic field as
shown. What is the direction
of the magnetic force?
2) into the page
3) zero
4) to the right
5) to the left
v
q
ConcepTest 28.2 Atomic Beams
A beam of atoms enters
x x x x x x x x x 1x x x
a magnetic field region.
x x x x x x x x x x x x
What path will the
x x x x x x x x x x x x
atoms follow?
x x x x x x x x x x x x
x x x x x x x x x x x x
4
x x x x x x x x x x x x
2
3
ConcepTest 28.3 Magnetic Field
A proton beam enters into a
magnetic field region as shown
below. What is the direction of
the magnetic field B?
1) + y
2) – y
3) + x
4) + z (out of page)
5) – z (into page)
y
x
ConcepTest 28.4a Mass Spectrometer I
x x x x x x x x x x x x
Two particles of the same mass
enter a magnetic field with the
same speed and follow the paths
shown. Which particle has the
bigger charge?
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
1
2
3) both charges are equal
4) impossible to tell from the picture
ConcepTest 28.4b Mass Spectrometer II
A proton enters a uniform
magnetic field that is
perpendicular to the
proton’s velocity. What
happens to the kinetic
energy of the proton?
1) it increases
2) it decreases
3) it stays the same
4) depends on the velocity direction
5) depends on the B field direction
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
ConcepTest 28.5 Velocity Selector
1) up (parallel to E )
What direction would a B field
have to point for a beam of
electrons moving to the right to
go undeflected through a region
where there is a uniform electric
field pointing vertically upward?
2) down (antiparallel to E )
3) into the page
4) out of the page
5) impossible to accomplish
E
B=?
electrons
v
ConcepTest 28.6a Magnetic Force on a Wire I
A horizontal wire carries a current
and is in a vertical magnetic field.
What is the direction of the force
on the wire?
1) left
2) right
3) zero
4) into the page
5) out of the page
I
B
ConcepTest 28.6b Magnetic Force on a Wire II
1) left
A horizontal wire carries a current
2) right
and is in a vertical magnetic field.
3) zero
What is the direction of the force
4) into the page
on the wire?
5) out of the page
I
B
ConcepTest 28.7a Magnetic Force on a Loop I
1) + x
A rectangular current loop is
2) + y
in a uniform magnetic field.
3) zero
What is the direction of the
4) - x
net force on the loop?
5) - y
B
z
y
x
ConcepTest 28.7b Magnetic Force on a Loop II
1) move up
If there is a current in
2) move down
the loop in the direction
3) rotate clockwise
shown, the loop will:
4) rotate counterclockwise
5) both rotate and move
B field out of North
B field into South
N
S
N
S