Two stationary positive point charges, charge 1 of magnitude 3.20nC and charge 2 of magnitude 2.00nC , are separated by a distance of 42.0cm . An electron is released from rest at the point midway between the two charges, and it moves along the line connecting the two charges.
What is the speed v-final of the electron when it is 10.0cm from charge 1?
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A 210 turn flat coil of wire 25.0 cm in diameter acts as an antenna for FM radio at a frequency of 100 MHz. The Magnetic field of the incoming electromagnetic wave is perpendicular to the coil and has a maximum strength of 9.30*10^-13 T.
What power is incident on the coil?
What average emf is induced in the coil over one-fourth of a cycle?
If the radio receiver has an inductance of 2.30 microH, what capacitance must it have to resonate at 100 MHz.
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Consider a head-on, elastic collision between a massless photon (momentum po and energy Eo ) and a stationary free electron.
a) Assuming that the photon bounces directly back with momentum p (in the direction of po ) and energy E, use conservation of energy and momentum to find p.
b) Verify that your answer agrees with that given by Compton's formula with theta = pi.
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One string of a certain musical instrument is 78.0cm long and has a mass of 8.78g . It is being played in a room where the speed of sound is 344 m/s.
Part A
To what tension must you adjust the string so that, when vibrating in its second overtone, it produces sound of wavelength 0.754m ? (Assume that the breaking stress of the wire is very large and isn
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Two identical conducting spheres, fixed in place, attract each other with an electrostatic force of -0.6825 N when separated by 50 cm, center-to-center. The spheres are then connected by a thin conducting wire. When the wire is removed, the spheres repel each other with an electrostatic force of 0.1986 N. What were the initial charges on the spheres? Since one is negative and you cannot tell which is positive or negative, there are two solutions. Take the absolute value of the charges and enter the smaller value AND larger value.
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If the wavefunction for a system is a superposition of wavefunction, the wavefunction of the system cannot be determined. Explain this statement.
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How do electric charges move in an electric field?
a. Positive charges move in the direction of the electric field, whereas negative charges move in the opposite direction
b. Negative charges move in the direction of the electric field, whereas positive charges move in the opposite direction
c. Both positive and negative charges move in the direction of the electric field
d. Both positive and negative charges move in the opposite direction of the electric field
e. It depends on the electric field
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A newspaper delivery boy is riding his bicycle down the street at 5.1m/s . He can throw a paper at a speed of 8.3m/s. What is the paper's speed relative to the ground if he throws the paper forward?
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A long, thin solenoid has 870 turns per meter and radius 3.00cm . The current in the solenoid is increasing at a uniform rate of 65.0A/s .
A)What is the magnitude of the induced electric field at a point 0.550cm from the axis of the solenoid?
B)What is the magnitude of the induced electric field at a point 1.00cm from the axis of the solenoid?
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The rear window in a car is approximately a rectangle, 2.4 m wide and 0.65 m high. The inside rearview mirror is 0.40 m from the driver's eyes, and 2.10 m from the rear window. What is the minimum length for the rearview mirror if the driver is to be able to see the entire width and height of the rear window in the mirror without moving her head? What is the minimum height for the rearview mirror if the driver is to be able to see the entire width and height of the rear window in the mirror without moving her head?
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Alice is driving a race car around an essentially circular track. Brian, who is sitting at a fixed position at the edge of the track, measures the time that Alice takes to complete a lap by starting his watch when Alice passes by his position (call this event E) and stopping it when Alice passes his positin again (call this event F). This situation is also observed by Cara and Dave, who are passengers in a train that passes very close to Brian. Cara happens to be passing Brian just as Alice passes Brian for the first time, and Dave happens to pass Brian just as Alice passes Brian the second time. Assume that the clocks used by Alice, Brian, and Cara are close enough together so that we can consider them all to be "present" at event E, and similarily that those used by Alice, Brian, and Dave are "present" at event F. Assume that the ground frame is an inertial reference frame.
Who measures:
a) the proper time,
b) the coordinate time,
c) and the spacetime interval between events E and F?
Explain why.
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A heat engine operates between a high-temperature reservoir at 610 K and a low-temperature reservoir at 320 K. In one cycle, the engine absorbs 6800 J of heat from the high-temperature reservoir and does 2200 J of work.
A) What is the net change in entropy as a result of this cycle?
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Brief timeline of the development of the theory and or technology and key players of the physics of Particle and Wave detection
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