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Exam 1 on FEB 12.2014- Phvsics105- R. Schad
YOUR NAME
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L.
This is to identify the exam versionyou have - IMPORTANT
Mark the A
2.
This is to identify the examversion you have - IMPORTANT
Mark the B
A ball is thrown up into the air. While the ball is in free fall, what doesits acceleration
do?
3.
E
4.
+
5.
A)
B)
C)
D)
increases
remainsconstant
increasesand then decreases
decreases
If a caris traveling nurthwaxl and slowing down, what is the directionof the
accelerationon the car that causesit to slow down?
1.
2.
3.
4.
5.
southward
eastward
northward
westward
neitherof these
If an
q
[graph shows acceleration[in m/s2 as a function of time in s]
At which time would it reachits largestpositivevelocity?
1. Alzeroseconds
2. At 1 second
/^\\^_^
(J.) /\t Z seconds
4. At 3 seconds
5. At 4 seconds
6.
n
A ball is thrown off a building with a straight horizontally initial velocity of 15 m/s.
When it hits the ground 20 m below, how far away from the foot of the building will it
be?
/r
m
02. 30.3
15.0m
D
xl-
)o
3tn
F
b.
c.
d.
e.
4.5N
9.0N
9.8N
3 . 0N
zeto
'F -
,f z |
=
pva
I
(*t
frZ
P
't -
/tt4,a -
*tu-
3
J.iiz c*"
The horizontal surface on which the objects slide is frictionless.
The left mass is 2 kg, the right 4 kg and the magnitude of the force F with which you
push the small block is 4.5 N,
determine the force the small block is exerting on the large block.
a.
8.
* v,*oS r ts
t c'
tr
t
35.0m
4. 9.8m
5. None of the above
J.
7.
'Yf:y
r^,)
1r=6,
I
4,
Y,)
,u" *f,2=4kt T-z
o
Which of the following cofiecYlydescribesthe centripetalaccelerationvector for a
particlemovingwith constantspeedon a circularpath?
A)
B)
c)
D)
constantand alwaysparallelto the velocity vector for the particle
magnitudeand alwaysperpendicularto the velocity vector
of constant
for the particle
of constantmagnitudeand alwaysparallel to the velocity vector of the
particle
constantand alwaysperpendicularto the velocity vector of the particle
. Jar
A ball was thrown such that its maximum height is 1,0m.
At this highest point it has a total velocity of L0 m/s.
What was the initial magnitude of the velocity it was thrown wi
1.. 10m/s
2.
'J"4m/s
A
l9l rzm/s
4. 24m/s
5. None of these
The free-body diagram of a mass on a horizontal plane with friction, being pushed to
the right at constant speed is most closely:
e) none of these
11.
€,
l(
U
30 kg]favoritetoy.
I A hippo [2000kg] is siuing on Johnny's [mro6ooy:
I The groundhasa coefficientof friction of trr: 0.5.
| Pushingthe hippo horizontally with all his might, till his feet slide, Johnnytries to move
I tne nippo away.Doesnot work.
What is the friction force the floor is exertingon hippo during this attempt?
1. Zerc
2. 147N
3. 9800N
4. 9947N
5. None of the above
r"
FPutor
?
rFt
rrypv
t r, / 4" <"po'
FaB
F=l---^'
I tV,^tu
' PR,'/"4r^",
-r
=2z
(
/oet n( no,t
'lo(o-/
5
)o
q.F /v
12.
A small rocket movesstraightup with a constantacceleration.
Then it cuts off the engineslit is still closeto earth,thus gravttyactsat regular
strengthl.Finally it hits the ground.
Which of the following graphsqualitativelycoffespondsto the scenariodescribed?
The
L
4-5
3.5
L.5
L
2.
J.
-1
-z
-3
-4
13.
4
You throw 2balIs, ball A vertically upwards, ball B with a 45 deg angle.They have the
sameinitial speed.
Which one would have the larger accelerationat the highestpoint?
L.A
2.8
3. They will have the sameacceleration.
L4.
B
If a rocket would fly according to the following graph, showing
vertical velocity [in m/s] as a function of time [in units of s] What would be the highest point?
3
2
1
tlon<
-2
-3
-4
1. 4m
f*-
U^
3. Zero
4. 16m
5. 42m
velocity
acceleration
gravitationalacceleration
v: dx/dt
a: dvldt
a: g:9.8 m/s2downwards
Kinematics
(1-dimensional)
Vf:Vi+a't
ProjectileMotion
(2-dimensional)
Vxf:
Xr: xi* v;'t* %'a'(
v? : viz + 2a'(xs- x1)
V y f : V y i+ a ' I
Vxi
,r ?:ur r ' +2ar ' ( yr - yi)
Xf : Xi l- V*i 't
Y r : Y i * v y i ' t+ l r ' a ' t 2
Newton'sLaw
F: m'a
Frz = - F21[action/ reactionin opposite
directionsl
Friction
Ffriction : FN F
Radial accelerationfor circular motion
Radial Force for circular motion
Hooke'sLaw (springforce)
quadraticequationx'r pX * q: 0
ap,6ia1: vtk
Fradial: mv'h
= -k x
Fsp11n,
x1,2:-pl2+ 1pzl4- q)t''

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