The figure shows two parallel nonconducting rings with their central axes along a common line. Ring 1 has uniform charge q1 and radius R; ring 2 has uniform charge q2 and the same radius R. The rings are separated by a distance 3.00R. The ratio of the electric field magnitudes of Ring 1 and Ring 2 at point P on the common line is 1.59. What is the ratio of charge magnitudes q1/q2?
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A bumper car with mass m1 = 115 kg is moving to the right with a velocity of v1 = 4.8 m/s. A second bumper car with mass m2 = 95 kg is moving to the left with a velocity of v2 = -3.8 m/s. The two cars have an elastic collision. Assume the surface is frictionless.
1. What is the velocity of the center of mass of the system?
2. What is the initial velocity of car 1 in the center-of-mass reference frame?
3. What is the final velocity of car 1 in the center-of-mass reference frame?
4. What is the final velocity of car 1 in the ground (original) reference frame?
5. What is the final velocity of car 2 in the ground (original) reference frame?
6. In a new (inelastic) collision, the same two bumper cars with the same initial velocities now latch together as they collide.
What is the final speed of the two bumper cars after the collision?
ANSWER THIS QUESTION IN PARTICULAR PLEASE. DO NOT PROVIDE A GENERALIZED SOLUTION.
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An unpolarized beam of light is incident on a pair of polarizing filters. The first filter set to polarize in the vertical direction and the second filter is set to polarize 38° from vertical. What is the intensity of the light beam after the second filter relative to the original beam?
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A 679-kg elevator starts from rest and moves upward for 3.30 s with constant acceleration until it reaches its cruising speed, 1.63 m/s. (a) What is the average power of the elevator motor during this period? (b) How does this amount of power compare with its power during an upright trip with constant speed?
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Determine the number of combined states, in the form of total |s m s >, for the combination of four spin ½ particles.
Do NOT determine the coefficients in the composite states.
Hint: make two combinations of spin - ½ particles, one for spins 1 and 2, and one for spins 3 and 4, and combine those
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A small conducting spherical shell with inner radius a and outer radius b is concentric with a larger conducting spherical shell with inner radius c and outer radius d. The inner shell has a total charge of -2q and the outer shell has a total charge of +4q.
Select True or False for the following statements.
The total charge on the inner surface of the small shell is
zero.
True False The total charge on the inner surface of the
large shell is zero.
True False The electric field in the region
r < a is zero.
True False The electric field in the region
r > d is zero.
True False The total charge on the outer surface of the
large shell is +2q.
True False The electric field in the region
c < r < d
is zero.
True False The total charge on the outer surface of the
small shell is -6q.
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Smarty McGuy intends to charge the parallel plate capacitor inside his intergalactic Ford Pinto (built by Doc Dre) with a lightning strike of 26x103 amps. Doc Dre's capacitor specifications are listed below:
The distance between the capacitor plates is 5 microns
The surface area of the capacitor plates is 3,844 cm2
There is a dielectric between the capacitor plates
What is the minimum dielectric constant of the material between the plates needed to store all the charge from the lightning assuming that the lightning strike lasts for 6x10-6 seconds and provides 1.21 Gigawatts of power? Assume the dielectric doesn't reach its breakdown voltage.
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(a) Name 4 major components of a Gamma camera. Briefly explain
the function of each component.
Also, describe the advantages and disadvantages of using “thin”
scintillating crystal.
(b) In an experiment with 51.80 MBq 99mTc, 5.88×105 counts are measured in 2 minutes. According to the manufacturer the sensitivity is 202 cnts/(min⋅μCi) (American manufacturers still use Ci instead of Bq, 1μCi = 37 kBq). What is the difference between the sensitivity of the measurement and the factory specification?
(c) in a NM scan, we use a specific contrast agent with half-life
of 2h and emitted gamma radiation with wavelength of the 8.79x0-12
m. We image the patient immediately after the injection and the
scan takes 20 minutes. Injecting 1 mCi, the acquired NM images have
signal-to-noise ratio of 40. Calculate the SNR if we inject the
patient with 3 mCi and scan him for 60 minutes.
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Explain two reasons behind the commercial failure of Low Earth Orbit satellite mobile communications companies (such as Iridium).
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An object with total mass mtotal = 14.8 kg is sitting at rest when it explodes into three pieces. One piece with mass m1 = 4.8 kg moves up and to the left at an angle of θ1 = 22° above the –x axis with a speed of v1 = 27.6 m/s. A second piece with mass m2 = 5.1 kg moves down and to the right an angle of θ2 = 27° to the right of the -y axis at a speed of v2 = 20.5 m/s.
What is the x-component of the velocity of the third piece?
What is the y-component of the velocity of the third piece?
What is the magnitude of the velocity of the center of mass of the pieces after the collision?
Calculate the increase in kinetic energy of the pieces during the explosion?
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A gas of nitrogen molecules is at a temperature of 1000K. In this case molecule has 3 translational, 2 rotational, and 2 vibrational degrees of freedom per molecule, i.e. a total of 7.
1.9. [1pt] Assuming the cycle operates as an engine, calculate the engine efficiency.
ANSWER
1.10. [1pt] If you are to build the most efficient engine using the highest and the lowest temperatures available from #9 how would the cycle look like on a PV-diagram [you need to indicate both cycles]
ANSWER
1.11 [1pt] What is the efficiency of the most efficient cycle in 1.10?
ANSWER
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Two charged particles attract each other with a force of magnitude F acting on each. If the charge of one is doubled and the distance separating the particles is also doubled, the force acting on each of the two particles has magnitude
(a) F/2
(b) F/4
(c) F
(d) 2F
(e) 4F
(f) None of the above.
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The electric field at a point in space is a measure of
(a) The total charge on an object at that point.
(b) The electric force on any charged object at that point.
(c) The charge-to-mass ratio of an object at that point.
(d) The electric force per unit mass on a point charge at that point.
(e) The electric force per unit charge on a point charge at that point.
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A charged insulator and an uncharged metal object near each other
(a) Exert no electric force on each other.
(b) Repel each other electrically.
(c) Attract each other electrically.
(d) Attract or repel, depending on whether the charge is positive or negative.
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The following hypothetical reaction shows a neutron (n) decaying into a proton (p+), an electron (e−), and an uncharged particle called an antineutrino
:

At first there is no charge, but then charge seems to be “created.” Does this reaction violate the law of charge conservation? Explain.
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