1) An antenna is connected to a car battery. Will the antenna emit electromagnetic radiation? Why or why not? Explain.

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1) An antenna is connected to a car battery. Will the antenna emit electromagnetic radiation? Why or why not? Explain. Only consider steady state, that is after the connection is made and not during initial or final disconnection.
2) A light-year is a measure of distance (not time). How many meters does light travel in a year?
3) How long does it take a laser beam to travel to the Moon and back? Take the Earth Moon distance to 384,000 km.
4) A beam of light is incident on a plane mirror at an angle of 35o. If the mirror rotates through a small angle through what angle will the reflected ray rotate? SHOW ALL WORK IN EITHER A DRAWING WITH THE GEOMERTY CLEARLY PROVING THE ANSWER YOU GIVE. NO WORK NO CREDIT!
5) The speed of light in polythene is 1.99 x 108 m/s What is the index of refraction of polythene?
6) A beam of light with red and blue components of wavelengths 670 nm and 425 nm, respectively, strikes a slab of fused quartz at an incident angle of 30o. On refraction, the different components are separated by an angle of 0.001312 rad. If the index of refractions of the red light is 1.4925, what is the index of refraction of the blue light? HINT: Be sure you convert radians to degrees to use Snell’s Law.

1) The walls of a blackbody cavity are at a temperature of 27o C. What is the frequency of the radiation of maximum intensity?

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1) The walls of a blackbody cavity are at a temperature of 27o C. What is the frequency of the radiation of maximum intensity?
2) Assume that a 100 – W light bulb gives off 2.50% of its energy as visible light. How many photons of visible light are given off in 1.00 min? (Use an average visible wavelength of 550 nm)
3) What is the energy of photons (joules) emitted by an 107.5-MHz FM radio station?
4) What is the longest wavelength of light that will emit electrons from a metal whose work function is 3.50 eV?
5) A metal with a work function of 2.40 eV is illuminated by a beam of monochromatic light. If the stopping potential is 2.5V, what is the wavelength of the light?
6) What is the de Broglie wavelength of a 1000 kg car moving at a velocity of 25 m/s?
7) A hydrogen atom in its ground state is excited to the n = 5 level. It then makes a transition directly to the n = 2 level before returning to the ground state.
a) What are the wavelengths of the emitted photons?
b) Would any of the emitted wavelengths be in the visible region?
8) What is the longest wavelength light capable of ionizing a hydrogen atom in the ground state?

1) The walls of a blackbody cavity are at a temperature of 27o C. What is the frequency of the radiation of maximum intensity?

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1) The walls of a blackbody cavity are at a temperature of 27o C. What is the frequency of the radiation of maximum intensity?
2) Assume that a 100 – W light bulb gives off 2.50% of its energy as visible light. How many photons of visible light are given off in 1.00 min? (Use an average visible wavelength of 550 nm)
3) What is the energy of photons (joules) emitted by an 107.5-MHz FM radio station?
4) What is the longest wavelength of light that will emit electrons from a metal whose work function is 3.50 eV?
5) A metal with a work function of 2.40 eV is illuminated by a beam of monochromatic light. If the stopping potential is 2.5V, what is the wavelength of the light?
6) What is the de Broglie wavelength of a 1000 kg car moving at a velocity of 25 m/s?
7) A hydrogen atom in its ground state is excited to the n = 5 level. It then makes a transition directly to the n = 2 level before returning to the ground state.
a) What are the wavelengths of the emitted photons?
b) Would any of the emitted wavelengths be in the visible region?
8) What is the longest wavelength light capable of ionizing a hydrogen atom in the ground state?

1. Where the acceleration is 0 and where the acceleration is highest in a swinging pendulum.

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1. Where the acceleration is 0 and where the acceleration is highest in a swinging pendulum.
2. Briefly explain in your own words why the pendulum oscillates.
3. Where is the kinetic energy highest? Please explain why that is so.
4. Write the equation for the pendulum’s period T. What characteristic(s) of the equipment affect the period?
5. Briefly explain why a pendulum makes a good clock.

1. A source of green light has a frequency of 6.2 x 1014 Hz. What is the wavelength in nanometers (nm) and in ?

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1. A source of green light has a frequency of 6.2 x 1014 Hz. What is the wavelength in nanometers (nm) and in ?
2. A flashlight beam has an exit power of 100mW, an exit diameter of 3.8cm, and a divergence of 1.1. Calculate the intensity in mW/cm2 at 55m and the size of the beam at that distance.
3. Suppose a 680-nm beam with a power of 0.2 mW and a 4.5-cm diameter strikes a detector with a 0.2-cm diameter. How many photons strike the detector per second?
A photomultiplier has a current gain of 3 x 106. A weak light beam produces 55 electrons/s at the photocathode. What anode-to-ground resistance must be used to get a 2.8 V voltage from the light pulse? The charge of an electron is 1.6 x 10-19 coulomb

1. A ruby laser emits light of wavelength 694.3 nm. If this light is due to transitions from the n=2 state to the n=1 state of an electron in a box (one dimensional), find the width of the box.

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1. A ruby laser emits light of wavelength 694.3 nm. If this light is due to transitions from the n=2 state to the n=1 state of an electron in a box (one dimensional), find the width of the box.
2. The normalized ground state wave function for the electron in hydrogen is
ψ(r, θ, φ) = π1/2a−3/2o e −r/ao
where r is the radial coordinate of the electron and ao is the Bohr radius. (a) Sketch the wave function as ψ(r) verses r. (b) Show that the probability of finding the electron between r and r + dr is given by 4πr2|ψ(r)|dr. (c) Show that the wave function is normalized. (d) Find the probability of locating the electron between x1 = ao/2 and x2 = 3ao/2.
3. A particle with kinetic energy E moves from a region where the potential is zero to one in which the potential is Vo, at x = 0, and E > Vo. (a) What happens classically? (b) What happens quantum mechanically? Derive the probabilities for reflection and transmission through the potential, leave your answer in terms of E and Vo.
Hint, the particle flux is velocity times probability amplitude and you should normalize the reflecting and transmitting flux by division of the incident flux of particles.