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Physics Review-Final Exam
Unit 7
1. A spring is attached to a 45kg mass. The spring is then stretched 18.4 cm and released on a frictionless
surface. The velocity of the mass when it reaches equilibrium is 15.2 m/s.
A. What is the kinetic energy of the mass at the equilibrium position?
B. What is the total energy of the mass?
C. What is the elastic constant of the spring?
D. What is the acceleration of the mass at its maximum displacement?
E. What is the velocity of the mass when it is half way from maximum displacement to equilibrium?
F. What would be the frequency of this oscillation?
2. A 45kg pendulum is placed on a 56cm long, massless, frictionless string. It is pulled back 18o from the
horizontal.
A. What is the tension on the string?
B. What is the accelerating force on the mass?
C. What would be the acceleration of this mass?
D. What is the potential energy of the bob?
E. What is the maximum velocity of the bob?
F. If the pendulum takes exactly 2.0 s for one complete oscillation, what is the acceleration due to gravity at
this point in the universe?
3. Draw a transverse wave and label all the parts.
4. Draw a longitudinal wave and label all the parts.
5. Explain what is meant by the terms
A. standing wave
B. node
C. loop
6. How many wavelengths is one loop?
7. A 6 m long string has a standing wave on it. If there are 5 nodes (including the ends), and the string is
vibrating with a period of 0.0077 s, what is the velocity of the wave in the string?
8. Draw a diagram with a wave that has an amplitude of 3.5 squares, and a wavelength of 5 squares. Draw a
second wave that has an amplitude of 2 squares and a wavelength of 4 squares. Finally, draw the wave
produced by the interference of those two waves.
8. Define
A.
B.
C.
D.
E.
Sound
Doppler Shirt (Doppler Effect)
Pitch
Octave
Loudness
F. Decibel
G. Sympathetic Vibration (Forced Vibration)
H. Natural Frequency
I. Resonance
J. Fundamental Frequency
K. Node
L. Loop
M. Harmonics
9. What kind of a wave is sound? How is it created?
10. What is the frequency shift of an object moving toward you? Away from you?
11. If an object is traveling toward you at a velocity of 25m/s and you are moving toward the source at 11 m/s,
what would be the frequency of the sound you hear if the source is producing a frequency of 410 Hz? Assume
that the temperature is 25oC.
12. What is the threshold of hearing? What is the threshold of pain? How many decibels is normal
conversation? At what point is damage being done to your ear?
13. What is the relative intensity of a sound wave that is 4.5 x 10-9 W/m2?
14. What is the intensity of a 67 db sound?
15. Assuming that the 67 db sound was measured 5.0 m from the source, what would be the sound intensity at a
distance of 11.4 m from the source?
16. What is the wavelength of the fundamental frequency on a string? In an open pipe? Closed pipe?
17. Which of the above can only produce odd harmonics? Why?
18. What is the fundamental frequency of an open pipe that is 11.4 cm long if the air temperature is 31oC?
What would be the fundamental frequency if the pipe were closed?
19. What are the first four harmonics produced by each of the pipes in #19?
20. What determines the quality of a sound that we hear? What determines the pitch?
Unit 8
1. State the law of reflection.
2. An object .904 cm is placed 17.2 cm in front of a convex mirror with a focal length of 15.0 cm.
A. What is the distance of the object?
B. What is the distance of the image?
C. What is the height of the object?
D. What is the height of the image?
E. What is the focal length of the mirror?
F. What is the radius of curvature?
G. How much does the mirror magnify the image?
H. If a ray of light struck the mirror with an angle of 18.2 degrees to the normal. What is the angle of
incidence?
I. What is the angle of reflection?
J. Is the image real or virtual?
K Is the image right side up or upside down?
3. To make life difficult. Repeat all the answers above, but use a convex mirror.
4. What happens to the angle of refractions if
a. the new medium slows down light
b. the new medium speeds up light
5. What is the speed of light in a medium if the index of refraction is 2.20?
6. What would be the angle of refraction of a ray that strikes the surface of zirconium from air at 18.4o?
7. What would be the angle of refraction of a ray if it came from diamond at an angle of 18.4 o, and entered
zirconium?
8. What would be the angle of refraction of a ray if it came from diamond at an angle of 18.4o, passed through
air and then struck a parallel piece of zirconium?
9. A converging lens with a focal length of 20.0 cm has an object placed 25 cm in front of it. Describe the
image.
10. The object is now moved so it is 15 cm from the lens. Describe the image.
11. The object is now placed 25 cm in front of a diverging lens with a focal length of 20.0 cm. Describe the
image.
12. The object is moved to 15.0 cm from the diverging lens. Describe the image.
13. What is the critical angle of zirconium? (ray into air)
14. Assuming that the sides of a zirconium cube are parallel, what is the maximum angle of incidence that will
allow light to travel through the cube? (assume it goes into air)
Ray Diagrams
Flat Mirror
Concave Mirror
Convex Mirror
Block of Diamond surrounded by air
Converging Lens
Diverging Lens
Unit 9
1. What conditions are necessary for light to exhibit signs of interference?
2. The distance between two slits is 2.5 x 10-5 m. The third order bright fringe is measured on a screen at an
angle of 4.25o from the central maximum. What is the wavelength of the light?
3. What would be the location of the 2nd and 4th order bright fringes?
4. What would be the frequency of this wave?
5. If the screen was 10.0 m from the slits, what would be the distance between dark fringes?
6. Why does diffraction occur?
7. Is diffraction a wave or particle property?
8. Monochromatic light with a wavelength of 600.0 nm shines at a right angle to a diffraction grating that
contains 250,000 lines per meter. What are the angles of the first and second order maxima?
9. What is the angle of the first order minima?
10. What is unique about laser light?
Unit 10
14
1. Object A has 3.00 x 10 extra electrons on it, object B has 5.00 x 1014 extra electrons it, and object C has
4.00 x 1014 extra electrons on it.
A. What is the charge in coulombs on each bear?
Object A –
Object BObject CB. Scared out of their pants, the bears attempt to hug each other, but are repelled by their electric fields.
If Object B is standing 0.466 m East of Object A, and Object C is 0.327 m Northeast of A at an angle
of 48.3o, what is the magnitude of the force between Object A and Object B?
C. What is the magnitude of the force between Object C and Object A?
D. What is the direction of the force between Object A and Object B? (actual value, not just repulsive or
attractive)
E. What is the direction of the force between Object A and Object C? (actual value, not just repulsive
or attractive)
F. What is the magnitude of the net force on Object A?
G. What is the direction of the net force on Object A?
H. The bears shift so that A is now east of Object B, and Object C is now west of Object B, and Object
A and Object C are 1.50 m from each other. Where must Object B be so that he has a net Field
Strength of 0 acting on it?
I. What would be the value of the Field Strength from Object C to Object B’s position at this point?
2. What is the electric field 2.4 cm away from a proton?
3. What would be the change in potential energy if the field in #2 was uniform, and an electron was moved 1.2
cm toward the proton?
4. If the electron and the proton were held in space 2.4 cm from each other, what would be the electrical
potential energy?
5. In both #3, and #4, what is the potential difference due to the proton?
6. Four 9.0 C charges are placed at the corners of a square 18 cm on a side. What is the electric potential
energy of the charge in the upper right corner?
7. What is the electric potential of the charge in the right corner?
8. What is a capacitor?
9. What is the potential difference across a parallel plate capacitor rated at 12.0 pF, if 8,000,000.0 electrons
charge on one plate.
10. What would have to be the surface area of that capacitor if only a vacuum was between the plates, and the
plates were 1.2 mm apart?
11. What would be the change in area of the capacitor if water (k = 80.0) was used as the dielectric?
12. Draw the symbol for a capacitor, resistor, light bulb, cell, 2 cells in parallel, 2 cells in series.
13. How much energy would be stored in the capacitor of problem #11?
14. Calculate the equivalent capacitance for the circuit below. Then calculate the potential, and current across
each capacitor.
12V
2F
3F
3F
5F
Unit 11
4F
Unit 11
1. What is the drift velocity of an electron?
2. How can energy be available immediately if energy is carried in the electrons, and they move so slowly?
3. State Ohm’s Law.
4. What is a kilowatt-hour a measurement of?
5. An electric car is designed to run on a bank of batteries with a total potential difference of 12 V and a total
energy storage of 2.0 x 107 J.
A. If the electric motor draws 8.0 kW, what is the current delivered to the motor?
B. If the electric motor draws 8.0 kW as the car moves at a steady speed of 20.0 m/s how far will the car
travel before it is “out of juice”?
6. Determine the amount of energy used by each appliance below.
A. a 75.0 W stereo
B. an electric oven that draws 20.0 A of current
C. a television with a resistance of 60.0 
7. An electric heater is operated by applying a potential difference of 50.0V across a nichrome wire of total
resistance 8.00 . Find the current in the wire and the power rating of the heater.
8. The current in a certain resistor is 0.50 A when it is connected to a potential difference of 110 V. What is the
current in this same resistor if
A. the operating potential difference is 90.0 V?
B. the operating potential difference is 130 V?
9. Find the current in the following devices when they are connected across a potential difference of 120 V.
A. a hot plate with a resistance of 48 
B. a microwave oven with a resistance of 20 
10. If a metal wire carries a current of 80.0 mA, how long does it take for 3.00 x 1020 electrons to pass a given
point on the wire?
11. In a particular television tube, the beam current is 60.0 A. How long does it take for 3.75 x 1014 electrons
to strike the screen?
12. A wire that is 14.2 m long, and has a diameter of 0.0876 cm is connected across a 12.0 V battery. The line
produces a current of 7.2 A. What is the resistivity of the wire?
13. What is the resistance of the following resistors
A. red blue black gold
B. green green green silver
C. grey brown orange gold
Unit 12
1. A proton named Phil (it’s a girl proton) is out taking a walk with Earl the boy electron. If they are jogging
along at 15,000m/s to the East when they encounter a 0.004 T magnetic field pointed North.
A. What is the magnitude and direction of the force on each of the particles?
B. What is the magnitude and direction of the acceleration on each of the particles?
C. What will be the radius of curvature for each of the particles?
D. One of the two will have a force directed upward on them, how fast (or slow) must this particle move to
exactly overcome the force of gravity?
E. Through what potential difference did Phil have to accelerate to produce a velocity of 15,000 m/s?
2. A 5.00A current is now placed through a wire. If the wire is placed in the same field as in problem 1, and
the current travels downward
A. What is the direction of the force on the wire?
B. If the wire has 25 cm place in the field, what is the magnitude of the force?
C. The same wire is taken out of the field and place so that its current points into this page. What is the
magnitude and direction of the magnetic field at a point that is 2.5 cm above it?
D. A second wire has the same current and is oriented, so the current points out of the paper. It is placed 15 cm
away from the first wire (to the left). What is the magnitude and direction of the force on the second wire?
E. What is the magnitude and direction of the field at a point P, that is exactly between the two, but 3.0 cm
above them?
P
3 cm
X
15 cm
3. A wire loop that is 20 cm long, and 10 cm wide is place in a magnetic field 0.500 T magnetic field.
A. What is the maximum magnetic flux possible with this setup?
B. What is the minimum magnetic flux possible with this setup?
C. The loop is placed perpendicular to the field and then pulled halfway out in 4.5 s. What is the induced emf?
D. The loop is now rotated from perpendicular to 45o in 2 seconds, what is the induced emf?
Unit 13
1. List the three nucleons and their charge values.
2. What are the number of protons, neutrons, and electrons in the following elements?
56
2
232
3
26 Fe
92 U
3. What is the mass of a neutron, proton, and electron?
4. If a nucleus has a mass of 4.0002u, what is the value in eV?
5. The mass of Tritium (1 proton, 2 neutrons, 1 electron) is 3.016 u. What is the binding energy of Tritum?
6. What is
a. Strong Nuclear Force –
b. Weak Nuclear Force –
7. List the following forces in order from strongest to weakest (Strong Nulcear, Weak Nuclear, Gravitational,
Electromagnetic).
8. What is a
a. alpha particle –
b. beta particle –
c. gamma ray –
9. Write the reaction for the alpha, beta, and gamma decay of 232
92 U .
10. What is a positron?
11. What is the decay constant if a sample with 2500 atoms has 12 atoms go through decay in a minute?
12. If the same type of atom was used with a sample of 13050 atoms, how many would be left that hadn’t
decayed after 2s?
13. What is the half life of this mystery atom?
14. 232
92 U goes through two alpha decays, then a beta, a gamma, and two more alpha decays. What is the
symbol for the element that is left at the end of this decay series?
Unit 14
Earth’s early defense system detects space aliens on board a large ship headed for earth. The ship is detected as
it crosses the orbit of Neptune (4.12 light hours away). The ship is traveling at the speed of 0.82c relative to the
Earth.
(A) How long has it taken the image of the ship to get to us?
(B) In that period of time, how far has the ship traveled relative to the earth?
(C) How long a period of time has it been on the ship?
(D) How far does the ship think it is to the Earth from Neptune?
As the ship passes an asteroid, it pulls out its super duper destructo beam gun and shoots the 45.0 Gg asteroid
into two pieces. The first part which is 32.5 Gg heads toward the sun at 0.750c.
(E)What is the velocity (magnitude and direction) of the rest of the asteroid?
(F) If you were sitting on one asteroid, how fast would the other one appear to be going away from you?
The alien spaceship shoots a warning missile toward the earth. The missile has a mass of 1250 kg and is
traveling at 0.500c relative to the spaceship.
(G) How fast does it travel relative to the Earth?
(H) How much energy was needed to accelerate the missile?
(I) The missile hits a giant shield that we have put in space totally annihilating the missile (converting
everything to energy). How much energy must the shield be capable of absorbing it if survives?
The aliens