SPH3UPhysicsStudyExam-January2011

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SPH3U Physics Study Exam
Part 1 – Short answer & problem solving (80 marks)
Please show all your work for full marks. Report your final answers in the space provided and
pay attention to units and significant digits.
1. The following table represent the data collected in a motion lab. Plot the data to produce a
velocity-time graph. (1.5 mks)
Time (s)
0.25
0.50
0.75
1.00
1.25
1.50
Velocity ( m/s)
3.7
5.7
7.9
9.9
12.1
14.3
15.0
Velocity
(m/s)
10.0
5.0
1.0
0.5
1.5
Time (s)
a ) At what speed did the object start the motion at 0.0 s? (1/2 mk)
Answer b ) Calculate the acceleration of the object’s motion. (1 mk)
Answer c ) Use the graph to determine the displacement of the object while it travelled from 0 – 1.5 s.
(3 mks)
Answer -
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2. A stone is dropped from a bridge that is 75.0 m above the water. The person waits 2.00 s after
releasing the stone and throws a second stone so that the two stones hit the water at the same
time. Calculate the initial velocity the second stone must be released with? (4 mks)
Answer 3. Explain if it is possible to drive a car around a circular arc without any acceleration. (2 mks)
4. A large 45.5 kg box is pushed along the floor at a constant velocity of 0.75 m/s [forward].
Calculate the coefficient of friction if the applied force is 375 N [forward]. (3 mks)
Answer Mark achieved on this page- _________
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5. As 7700 kg airplane glides to a landing. It has a 12500 N [down] force of gravity pulling it
toward the Earth’s surface and a 58800 N [horizontally forward] force of lift acting on it.
a ) At what angle, relative to the horizontal, does the airplane approach the ground? (1 mk)
Answer b ) What is the magnitude of acceleration for the airplane as these forces act on it? (2 mks)
Answer 6. Describe a situation where an object is in motion but no physical work is being accomplished.
Explain why there is no work being done in this case. (2 mks)
7. A 75.0 g arrow is fired vertically into the air. At a point in its flight, it is determined that the
arrow has 33.4 J of gravitational potential energy. How high above the surface of the Earth is it
with this energy? (3 mks)
Answer Mark achieved on this page- _________
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8. A candle has 7525 J of energy stored in its chemical bonds. That energy is used to heat 150 g of
o
water, which has a starting temperature of 21.0 C. Calculate the final temperature of the water
o
if all the energy is transferred to the water. The specific heat capacity for water is 4186 J/kg C.
(3 mks)
Answer 9. Use graphing techniques to determine how much work is required to stretch an elastic bungee
cord to a final length of 6.0 m. (3.5 mks)
Force (N)
2000
1500
1000
500
2
Length (m)
4
6
Answer 10. An elevator has a motor that can produce 25000 W. If this power were used to raise an 850 kg
elevator to a height of 35.5 m, how much time would be required for the motion? (3 mks)
Answer Mark achieved on this page- _________
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o
11. A tow truck pulls a car by a cable that makes an angle of 30 to the
3
horizontal. The force applied to the tow cable is 7.2 x 10 N. How
much work is done in pulling the car horizontally 5.5 km?
(3 mks)

Fapplied
o
30
Answer 12. A wave with an amplitude of 50.0 cm travels down a 7.75 m spring in 3.00 s. The student who
creates the wave moves their hand through 4 cycles in 1.00 s. Calculate the wavelength of the
wave? (3 mks)
Answer 13. When two tuning forks are vibrating at the same time one observes that the sound grows louder
then softer at regular intervals. The change in volume occurs at a rate of exactly 48 times in
16.0 s. If one tuning fork is known to have a frequency of 256.0 Hz, what are the two possible
frequencies of the second tuning fork? (3 mks)
Answer Mark achieved on this page- _________
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14. A vibrating tuning fork with a frequency of 324 Hz is held over a tube of air whose length can
be adjusted by raising and lowering a column of water in the tube. The starting length of the
column of air is very short and letting the water out slowly gradually lengthens it. If the speed
of sound in air is 336 m/s, how long is the column of air when the first constructive interference
is heard. (4 mks)
Answer 15. A cannon is fired from a distant hilltop and you see the smoke followed by hearing the
explosion. Calculate how far away the cannon is if the temperature on the day this is observed
o
is 18 C and time between the smoke and the sound is 4.7 s. (2 mks)
Answer 16. An astronaut stands on the edge of a lunar crater and throws a half-eaten Twinkie™ horizontally
with a velocity of 5.00 m/s. The floor of the crater is 100.0 m below the astronaut. What
horizontal distance will the Twinkie™ travel before hitting the floor of the crater? (The
acceleration of gravity on the moon is 1/6th that of the Earth). (5 mks)
Answer Mark achieved on this page- _________
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17. A rifle is fired horizontally and the bullet travels 200.0 m [E]. The rifle barrel is 1.90 m from the
ground. At what speed was the bullet travelling? Ignore friction. (4 mks)
Answer 18. The following are the masses of H, Li and He atoms:
H: 1.0073 atomic mass units
Li: 7.0160 atomic mass units
He: 4.0015 atomic mass units
An atomic mass unit, symbol u, is equal to 1.6605 x 10–27 kg.
The mass decreases in the following reaction:
1
7
4
1H  3Li  2
He  24He.
a) Calculate ∆m in atomic mass units and in kilograms. (4 mks)
Answer b) How much energy results from this change? (1 mk)
Answer 19. A skater is travelling 5.7 m/s [E] when she makes a turn. In 2.75 s the skater’s velocity has
changed to 3.9 m/s [N]. Calculate the average acceleration of the skater. (4 mks)
Answer Mark achieved on this page- _________
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20. A coil consists of exactly 250 loops with each loop having a circumference of 10.5 cm. The coil
is moved through a magnetic field, which has a strength of 0.457 T. The force moving the coil
through the magnetic field as a magnitude of 10.8 N. The magnetic field acts to the right (east)
and the motion of the coil is downward (south). Calculate the magnitude (size) and direction of
the current in the coil? (5 mks)
Answer – Magnitude-
Direction-
21. A transformer has a power of 2750 W and an input current of 25 A. There are 2500 loops in the
output coil and it delivers an output voltage of 12.0 V.
a ) Calculate the input coil voltage. (2 mks)
Answer b ) Determine the number of loops in the input coil. (2 mks)
Answer 22. Label the current and the north pole of the magnetic field in each coil. (2 mks)
G
This magnet is being
pulled away.
N
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23. Use the diagram below to answer the following questions. (3 mks)
a ) What device does the diagram represent?
b ) Label the following items referred to in the diagram.
i ) “B” is called ii ) “E” is called iii ) “A” is called -
D
c ) Which way is the current flowing through “D”?
Left-to-right or right-to-left (circle one)
d ) The magnetic pole at the location marked “X” is
north / south. (circle one)
E
B
S
N
A
A
C
X
Rotation
24. A lifting magnet has a magnetic field strength of 2500 T. Simultaneously, the number of loops
is tripled, the voltage is doubled, the current is reduced to ¼ the original current and the
magnetic permeability of the core is doubled. If the resistance of the coil is unaffected,
determine the new magnetic field strength of the magnet under the new conditions. (2 mks)
Answer -
Mark achieved on this page- _________
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Part 2 – Multiple Choice (20 marks)
Select the best answer for each question. You may write on these questions but be sure to record
your final selections on the provided Scantron sheet.
1. Which of the following values is a scalar value?
a ) velocity
b ) time
c ) displacement
d ) force
e ) acceleration
2. Which of the following velocity-time graphs represents the motion of an arrow, which is fired
vertically upward, upon leaving the bow?
v
v
t
t
a)
v
v
c)
b)
t
t
d)
3. Which of the following fundamental forces is the weakest?
a) Gravitational b) Weak
c) Strong
d) Electromagnetic
nuclear
nuclear
4. Which of the following vectors represents the resultant
force acting on object “X”?
X
a)
b)
c)
d)
v
e)
e)
t
Frictional
e)
5. As a truck moves down the road the driver slams on the brakes to avoid hitting a cat. The fuzzy
dice hanging on his mirror swing toward the window. The motion of the dice show
a) Newton’s
b) Newton’s
c) Newton’s d) the universal e) cats are “big
first law of
second law
third law
law of
time” trouble.
motion.
of motion.
of motion.
gravitation.
6. Which of the following are equivalent to a watt (W)?
a) (kg m)/s3
b) (N m)/s
c) (kg J)m
d) (C V)/
e) (kg m3)/s2
7. Which of the following forms of energy is a form of potential energy?
a) sound
b) thermal
c) nuclear
d) radiant
e) mechanical energy
8. As you sit on the stool in the science lab, you place your hand on the metal leg of the stool and
o
the wooden counter top. The science lab has been maintained at 18 C for the past week. Apply
the concept of thermal equilibrium to identify the correct statement.
a) The leg of
b) The wooden
c) The leg and
d) Thermal
e) It is impossible
the stool’s
counter top’s
the counter
equilibrium
to determine
temperature
temperature
top are both
predicts that cold
which object will
is less than
is greater than
at a
will flow to the
be cooler without
o
o
temperature
object
with
the
knowing their
18 C.
18 C.
o
lowest
specific
specific heat
of 18 C
heat capacity.
capacities.
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9. A student throws their physics text vertically upward. As the textbook rises, which of the
following quantities increases?
a) mechanical
energy
b) speed c) acceleration d) kinetic
energy
e) gravitational potential
energy
10. The main reason the Tacoma Narrows bridge collapsed was
a) extremely
powerful
winds just
blew it down.
b) the steel
used was
of
inferior
quality.
c) certain wind
speeds caused the
bridge to vibrate
at its natural
frequency.
d) the bridge
design did not
account for
fixed end
reflections.
e) a suspension
bridge design
should never be
used to span a
canyon.
11. The frequency range for human hearing is approximately
a) 2 Hz to
2000 Hz.
b) 20 Hz to
20 000 Hz.
c) 200 Hz to
200 000 Hz.
d) 2 Hz to 2 kHz.
e) 2 kHz to 2 MHz.
12. An ambulance races toward you with the siren sounding. The property of sound that accounts
for the siren sounding different as it approaches as compared to when it departs is
a) resonance. b) a standing
c) frequency beats.
d) nodal lines.
wave.
13. What happens during positron emission?
a) A proton is converted to a neutron and an electron.
b) A neutron is converted into a proton and a positron.
c) A proton is converted into a neutron and a positron.
d) The atomic number increases.
e) The mass number increases.
e) the Doppler effect.
14. What happens to the mass of an atom when it undergoes alpha
decay?
a) The mass number decreases by 2.
b) The mass number decreases by 4.
c) There is no change in mass.
d) There is no change in atomic number.
15. To hold the nucleons together in the nucleus, energy is required. What is the name of this
energy?
a) free energy b) thermal energy c) kinetic energy d) binding energy e) valence energy
16. A sample of Radon-222 has a half-life of 3.82 days. After 11.46 days there are 5g remaining.
How much Radon-222 was in the original sample?
a) 10g
b) 80g
c) 40g
d) 125g
e) 25g
17. Which of the following materials would be the best choice for the core of an electromagnet?
a) Aluminum
b) Iron
c) Copper
d) Air
e) All of the materials would work as well
in the core of an electromagnet.
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18. Which of the following situations represents the correct relationship between the current,
magnetic field and force acting on the conductor?
a)
b)
Force
N
S
d)
e)
Force
S
Force
S
N
N
S
N
c)
Force
Force
N
S
19. Mechanical energy is converted to electrical energy by using which of the following
electromagnetic technologies.
a) generator
b) transformer
c)
motor
d) electromagnetic relay
e)
galvanometer
20. Which of the following compass needles is accurately representing the direction of the magnetic
field associated with this coil?
E
C
A
B
D
a)
A
b) B
c)
C
d) D
e)
E
Mark achieved on this page- _________
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