This preview shows pages 1–2. Sign up to view the full content.
1
This printout should have 11 questions.
Multiplechoice questions may continue on
the next column or page – fnd all choices
beFore answering.
001 (part 1 of 2) 10.0 points
You weigh 250 lb.
How much would you weigh iF you were
standing on a mountain 200 km tall (equiva
lent to standing still at about the altitude oF
a space shuttle orbit)? The gravitational con
stant is 6
.
67
×
10
−
11
N
·
m
2
/
kg
2
, the radius
oF the Earth is 6
.
4
×
10
6
m, the mass oF the
Earth is 6
×
10
24
kg, and the acceleration due
to gravity is 9
.
8 m
/
s
2
. 4.45 N = 1 lb.
Correct answer: 1042
.
95 N.
Explanation:
Let :
W
= 250 lb
,
h
orbit
= 200 km = 2
×
10
5
m
,
r
E
= 6
.
4
×
10
6
m
,
and
G
= 6
.
67
×
10
−
11
N
·
m
2
/
kg
2
.
The gravitational acceleration at an alti
tude oF 200 km is
g
′
=
GM
E
r
′
2
=
GM
E
(
r
E
+
h
orbit
)
2
=
(6
.
67
×
10
−
11
N
·
m
2
/
kg
2
) (6
×
10
24
kg)
(6
.
4
×
10
6
m + 2
×
10
5
m)
2
= 9
.
18733 m
/
s
2
.
Your weight is
W
= 250 lb
×
4
.
45 N
lb
= 1112
.
5 N
,
so your mass is
m
=
W
g
=
1112
.
5 N
9
.
8 m
/
s
2
= 113
.
52 kg
.
At an altitude oF 200 km, your weight would
be
W
′
=
mg
′
= (113
.
52 kg) (9
.
18733 m
/
s
2
)
=
1042
.
95 N
.
002 (part 2 of 2) 10.0 points
How much does this di±er From your weight
on the surFace oF the Earth?
Correct answer: 15
.
6294 lb.
Explanation:
W W
′
= 1112
.
5 N

1042
.
95 N
= 69
.
5508 N
×
1 lb
4
.
45 N
=
15
.
6294 lb
,
which would be easily detected on a bathroom
scale.
003
10.0 points
Three masses are arranged in the (
x, y
)
plane as shown.
4 kg
4 kg
5 kg
y
(m)
1
3
5
7
9
x
(m)
1
3
5
7
9
What is the magnitude oF the resulting
Force on the 4 kg mass at the origin? The
value oF the universal gravitational constant
is 6
.
6726
×
10
−
11
N
·
m
2
/
kg
2
.
Correct answer: 8
.
62063
×
10
−
11
N.
Explanation:
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview. Sign up
to
access the rest of the document.
 Summer '08
 Staff
 Physics

Click to edit the document details