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pasha (sep635) – HW #12 – Antoniewicz – (56445)
1
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001 (part 1 of 7) 3.0 points
A spacecraFt is observed to be at loca
tion
h
200 m
,
300 m
,

400 m
i
relative to an
origin located on a nearby asteroid, and
5sl
a
t
e
ri
ti
so
b
s
e
r
v
e
dt
ob
ea
tl
o
c
a
t
i
o
n
h
425 m
,
25 m
,

650 m
i
.
±ind the average ve
locity oF the spacecraFt, ¯
v
=
h
v
x
,v
y
,v
z
i
.
What is
v
x
in m/s?
Correct answer: 45 m
/
s.
Explanation:
The average velocity oF the spacecraFt is
calculated by fnding the change oF position
over a change in time:
¯
v
=
~
r
f

~
r
i
Δ
t
.
Because
~
r
is a vector, the average velocity will
also be a vector and each component must be
calculated separately.
±or ¯
v
x
the value becomes:
¯
v
x
=
v
2
x

v
1
x
Δ
t
=
(425 m)

(200 m)
(5 s)
=
45 m
/
s
002 (part 2 of 7) 3.0 points
What is
v
y
in m/s?
Correct answer:

55 m
/
s.
Explanation:
The average velocity oF the spacecraFt is
calculated by fnding the change oF position
over a change in time:
¯
v
=
~
r
f

~
r
i
Δ
t
.
Because
~
r
is a vector, the average velocity will
also be a vector and each component must be
calculated separately.
±or ¯
v
y
the value becomes:
¯
v
y
=
v
2
y

v
1
y
Δ
t
=
(25 m)

(300 m)
(5 s)
=

55 m
/
s
003 (part 3 of 7) 2.0 points
What is
v
z
in m/s?
Correct answer:

50 m
/
s.
Explanation:
The average velocity oF the spacecraFt is
calculated by fnding the change oF position
over a change in time:
¯
v
=
~
r
f

~
r
i
Δ
t
.
Because
~
r
is a vector, the average velocity will
also be a vector and each component must be
calculated separately.
±or ¯
v
z
the value becomes:
¯
v
z
=
v
2
z

v
1
z
Δ
t
=
(

650 m)

(

400 m)
(5 s)
=

50 m
/
s
004 (part 4 of 7) 4.0 points
What is

~
v

in m/s?
Correct answer: 86
.
8907 m
/
s.
Explanation:
The magnitude is calculated by:

~
v

=
q
v
2
x
+
v
2
y
+
v
2
z
=
q
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View Full Document pasha (sep635) – HW #12 – Antoniewicz – (56445)
2
Find the unit vector in the direction of the
velocity of the spacecraft, ˆ
v
=
h
ˆ
v
x
,
ˆ
v
y
,
ˆ
v
z
i
.
What is ˆ
v
x
?
Correct answer: 0
.
517892.
Explanation:
The unit vector for a vector is given as :
ˆ
v
=
h
ˆ
v
x
,
ˆ
v
y
,
ˆ
v
z
i
=
h
v
x
,v
y
,v
z
i

~
v

For example:
ˆ
v
x
=
v
x

~
v

=
45 m
/
s
86
.
8907 m
/
s
=
0
.
517892
006 (part 6 of 7) 3.0 points
What is ˆ
v
y
?
Correct answer:

0
.
632979.
Explanation:
The unit vector for a vector is given as :
ˆ
v
=
h
ˆ
v
x
,
ˆ
v
y
,
ˆ
v
z
i
=
h
v
x
,v
y
,v
z
i

~
v

For example:
ˆ
v
y
=
v
y

~
v

=

55 m
/
s
86
.
8907 m
/
s
=

0
.
632979
007 (part 7 of 7) 2.0 points
What is ˆ
v
z
?
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This note was uploaded on 11/17/2011 for the course PHY 303K taught by Professor Turner during the Fall '08 term at University of Texas at Austin.
 Fall '08
 Turner

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