Physics Final Exam
A force of 5 Nanda force of 15 N acting on an
object can produce the following net forces except
•
20 N
•
15 N
•
10 N.
•
5 N.
While deciding where to drive a supporting nail, you
are pressing a 18-N picture frame against the wall
to keep it from falling. What is the minimum force
perpendicular to the wall that you must exert on the
frame to keep it stationary? The coefficient of
kinetic friction for the two surfaces in contact is
0.42.
A 1.0 x 10"4 kg spacecraft is traveling through
space with a speed of 1200 m/s relative to Earth. A
thruster fires for 2.0 min, exerting a continuous
force of 25 kN on the spacecraft in a direction
opposite the spacecraft's motion.
Calculate the initial momentum and the final
momentum of the spacecraft.
An object thrown into the air stops at the highest
point in its path. Is it in equilibrium at this point?
Explain.
A 9.0 kg potted plant slides down a 25.0° incline
with an acceleration of 2.4 m/s. What is the
coefficient of kinetic friction between the potted
plant and the incline?
a 0.013
b. 0.012
C.
0.20
d. 0.24
The student in item 1 moves the box up a ramp
inclined at 12° with the horizontal.
If the box starts from rest at the bottom of the ramp
and is pulled at an angle of 25.0° with respect to
the incline and with the same 185 N force, what is
the acceleration up the ramp? Assume that
coefficient of k = 0.27.
A 75 kg box slides down a 25.0° ramp with an
acceleration of 3.60 m/s?.
a. Find coefficient of k, between the box and the
ramp.
b. What acceleration would a 175 kg box have on
this ramp?
A box of books weighing 325 N moves at a constant
velocity across the floor when the box is pushed
with a force of 425 N exerted downward at an angle
of 35.2° below the horizontal. Find coefficient of k,
between the box and the floor.
A man lifted a 281.5 kg load off the ground using his
teeth. Suppose he can hold just three times that
mass on a 30.0° slope using the same force. What
is the coefficient of static friction between the load
and the slope?
The muscle responsible for closing the mouth is the
strongest muscle in the human body. It may be able
to exert a force great enough to lift a mass of 400
kg. The force of biting has been recorded at 4.33 x
10"3 N. If each force shown in the diagram below
has a magnitude equal to the force of the bite,
determine the net force.
A 0.025 kg golf ball moving at 18.0 m/s crashes
through the window of a house in 5.0 x 10"-4 s.
After the crash, the ball continues in the same
direction with a speed of 10.0 m/s. Assuming the
force exerted on the ball by the window was
constant, what was the magnitude of this force?
What impulse was delivered to the ball?
Questions 4-9 refer to the following velocity-time graph of a jogger. The positive
dlN<lion Is -ay from the joggel's home.
+
·o
0
J
B
C
0
E
0
D
F
G
Time
___ 4. The jogger is at rest during which inteival?
a. AB
c. DE
b. BC
d. EF
<"01,yriW\l Oby Jloh, Rinrhan and Win.'llon.. All rtJthls r1•iw•rwcl.
Holt Physics
9
Name _ _ _ _ _ _ _ _ _ _ __
Class _ _ _ _ __
IMotion in One Dimension continued
Quiz
Date _ _ _ __
___ 5. During which of the following inteivals does the jogger have a constant positive velocity?
a.BC
b.CD
c. DE
d. FG
___ 6. During which intetval is the magnitude of the jogger's acceleration the
greatest?
a. AB
b.BC
c. DE
d. EF
7. During which of the following inteivals is the speed of the jogger
decreasing?
a. AB only
b. AB and CD
c. AB, CD, and EF
d. EFonly
___ 8. During which of the following inteivals is the jogger·s motion toward
home?
a. CD and EF
b. DE only
c. EF only
d. EFand FG
9. Rank the four displacements for the time intervals CD, DE, EF, and FG in
decreasing order. Explain your answer.
·rd Perched on the swing shown in the diagram
fill' !)I s of 52.0 g, and the base of the sWing has a
,3. 1 ·1 n1as
•
db' d
. .
1;1~ • • i,;3 g. The swing an
u are onginally at rest,
-ot
Ia
ffh
.
1
111: ~!,
the bird takes o onzontally at 2.00 m/s.
d(11en
.
.
an • h will the base of the swmg nse above its
tJcl\f 111g
d fr' .
11
. • al level? Disregar
1ction.
11
ongI
8.00 cm