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1. A nucleus in an excited state emits a -ray photon of energy 1 MeV.a) What is the photon frequency?b) What is the photon wavelength?c) How does the wavelength compare with typical nuclear radii (of the order of 10-15m)?

2. a) In the photoelectric effect, what is the relation between the threshold frequency and thework function?

b) A photoelectric surface has the work function of 4.00 eV. What is the maximum speed of thephotoelectron emitted by the light of frequency 3X10

15Hz?

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3. A charged particle entered into the magnetic field with velocity (v) at right angle.(a)Describe what F, v and B are as well as their orientation with respect to each other.

. (1/4 pnt)

(b)What does the magnetic field do to the trajectory of an electron? Explain.. (1/4 pnt)

4. Someone tells you that in their spectroscopy measurements they find a violet line that theybelieve corresponds to Hydrogen. Their measurements for that line were verified to be SA = 90

cm, SB = 30 cm, and d = 4134 nm.

a) What is the wavelength (in units of nm) and color actually observed? Show your calculation.. (3/4 pnt)

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b) What source is this most likely to be?. (3/4 pnt)

5. Given the setup below, with a magnet oriented as noted and a current carrying wire instantlyturned on with current I passing through the magnetic field.

(The wire is parallel to the ground.)

If it helps you picture it: imagine I in the direction of x (into the page) and B in the direction of

y (right to left).

a.) Describe the orientation of F, I and B with respect to each other.In terms of motion, what does

a magnetic field do to a moving electric charge? (hint: what is the direction of the resultant force)

.(0.5 pnt)

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b.) A 3D set of axes are drawn below. With respect to the diagram above, clearlydraw on

the axes the directions of: the current from the battery, the magnetic field, and the

resultant magnetic force. .(0.5 pnt)

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Referring to the following circuit:

If the voltage drop across the diode is 0.62 V find;

a- The voltage across each resistor? ........1 point

b- The current through the each resistor? ........0.25 point

6. A circular coil of area 0.00503 m2 consisting of 500 loops is placed between a uniform magneticfield which is perpendicular to the plane of the coil, and increasing at a rate of 0.2 T per second.

What is the resulting induced emf? (hint: Faradays law)

10V

10 ;

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7. The wavelengths of the visible spectrum are approximately 400nm to 700nm. Find the angularbreadth of the first order visible spectrum produced by a plane grating having 6000 lines per

centimeter, when white light is incident normally on the grating. (hint: d sin() =)