This preview shows pages 1–2. Sign up to view the full content.
1
This printout should have 19 questions.
Multiplechoice questions may continue on
the next column or page – fnd all choices
beFore answering.
001
10.0 points
Highway saFety engineers build soFt barriers
so that cars hitting them will slow down at a
saFe rate. A person wearing a saFety belt can
withstand an acceleration oF 300 m
/
s
2
.
How thick should barriers be to saFely stop a
car that hits the barriers at 86 km
/
h? Answer
in units oF m.
002
(part 1 oF 3) 10.0 points
Consider the velocity curve oF a one dimen
sional motion along the
x
axis.
The initial position is
x
= 10 m. The scale
on the horizontal axis is 2 s per division and
on the vertical axis 2 m/s per division.
b
b
b
b
b
a
b
c
time
×
(2 s) per division
velocity
×
(2 m/s) per division
The position at
t
= 4 s is given by
1.
x
= 30 m
2.
x
= 14 m
3.
x
= 18 m
4.
x
= 10 m
5.
x
= 24 m
6.
x
= 22 m
7.
x
= 12 m
8.
x
= 16 m
9.
x
= 28 m
10.
x
= 20 m
003
(part 2 oF 3) 10.0 points
The average velocity
v
between 0 s and 6 s is
given by
1.
5 m
/
s
<
v
≤
6 m
/
s
2.
1 m
/
s
<
v
≤
2 m
/
s
3.
8 m
/
s
<
v
≤
9 m
/
s
4.
7 m
/
s
<
v
≤
8 m
/
s
5.
3 m
/
s
<
v
≤
4 m
/
s
6.
4 m
/
s
<
v
≤
5 m
/
s
7.
6 m
/
s
<
v
≤
7 m
/
s
8.
9 m
/
s
<
v
≤
10 m
/
s
9.
2 m
/
s
<
v
≤
3 m
/
s
10.
0 m
/
s
<
v
≤
1 m
/
s
004
(part 3 oF 3) 10.0 points
The average acceleration
a
between 14 s and
16 s is given by
1.
0 m
/
s
2
<
a
≤
1 m
/
s
2
2.

3 m
/
s
2
<
a
≤ 
2 m
/
s
2
3.
3 m
/
s
2
<
a
≤
4 m
/
s
2
4.

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.
 Spring '09
 Staff
 Physics

Click to edit the document details