Problem 1
The figure below shows a side view of a flat surface with area 3.0 cm/\2 in a unifonn
magnetic field. If the magnetic flux through this area is 0.90 mWb, calculate the
magnitude of the magnetic field, and find the direction of the area vector (use magnetic
flux.. .it's just like electric flux).
Problem 2
There is almost no helium in ordinary air, so helium sprayed near a leak in a vacuum
system will quickly show up in the output of a vacuum pump connected to such a system.
You are designing a leak detector that uses a mass spectrometer to detect He+ ions
(charge +e=+1.602*I0/\-19C, mass 6.65*10/\-27 kg). The ions emerge from the velocity
selector with a speed of 1.00*10/\5mfs. They are curved in a semicircular path by a
magnetic field B and are detected at a distance of 10.16 cm from the slit S in the figure
below. Calculate the magnitude of the magnetic field B.
-
!CC/q
y - - ."
~
1
\
\
~
'-
-
.'J:::j. ( I c),," ~(ol '"')
-.t.
-- '".
.t
5
1'-
.-.',.-.,..1
1,(.
Z
Ob ""CO
# .," .,. .
tJ
"
if)
;:
t"1
v-
-=7 (j = ~
t
r.J3
\J
::76
; [",-,,"'10 -t.1k,) ( Iy:(c>'i"'1;)
(t. c.'1«0-1,c.. )(
$'.0 1.do-Z 1"'1)
=7[1)':;. o~11 r 1
Problem 3
A thin, horizontal copper rod is 1.00 m long and has a mass of 50.0 g. What is the
minimum current in the rod that can cause it to float in a horizontal magnetic field of 2.00
T?
1..f
1-~
~
(oJ,.,
Jf~-kJ '-'1.f'-VJc:-J
""'~') h f
:.7'-
4f
(L
fG'J.
1 - LA1~.'"f3
{loA,
~
(Lc..
~..v<. t\
r~\(";),
f7)
'L
I
'[l.-(
~ C) M- ,; "c..
tv r~
""j"",,"k
~t,..1
1 L $""
'"
1,.., ..
;;
(. ~ '5 Ie.,)( "I. '60 ""/~ )
(2.001")(
e
' ,
,..,'11, "'
13
::-,
R..
;"'I
1.00,.,)
~
,Nt
""'''''..). ~
Ju ~
J
~/""",-
l
,..., (j ~ /
I