Planetary orbits are circles.
Indicate whether the statement is true or false
[Ques. 2] What is the relationship between Bohr's model and the characteristic spectral lines of gases?
a. None. Bohr's model does not explain spectral lines.
b. The spectral lines are determined by the size of the initial orbit.
c. The spectral lines are determined by the various orbital jumps electrons can make.
d. The spectral lines are determined by the absorption of photons by the atom.
e. The spectral lines are determined by the angles at which electrons are emitted when light hits them.
[Ques. 3] If a body were in orbit very near the surface of the earth, its centripetal acceleration would be equal to g.
Indicate whether the statement is true or false
[Ques. 4] Which is the first postulate of Bohr's model of the atom?
a. The angular momentum of the electron is quantized.
b. Light is quantized.
c. An electron radiates while it remains in an allowed orbit.
d. An electron is not in a precise orbit.
e. A photon is emitted whenever an electron jumps up one orbit.
[Ques. 5] A body on the surface of the earth weighs 400 lb. The radius of the earth is about 4,000 miles. If this same body were placed on a 4,000 mile high tower, its weight would be 200 lb.
Indicate whether the statement is true or false
[Ques. 6] Which of these was NOT a difficulty initially met in explaining the photoelectric effect?
a. The transferred kinetic energy seemed to work too quickly.
b. If light is a wave, its amplitude should have governed the energy imparted to electrons to cause their emission, and frequency should have had the effects it had.
c. Increased intensity of the light did not increase the maximum kinetic energy of emitted electrons.
d. Increased frequency of the light increased the maximum kinetic energy of the electrons.
e. Electrons could not escape from solid materials.
[Ques. 7] As you go higher and higher above the surface of the earth, the mass of a body stays constant.
Indicate whether the statement is true or false
[Ques. 8] What is the photoelectric effect?
a. The mechanism by which a camera works.
b. The effect seen by bombarding a metal surface with an electron beam.
c. The production of light by an electric discharge through a gas.
d. The emission of electrons from a clean metal surface when light shines on the surface.
e. The fact that electrons bounce off any surface when light shines on it.
[Ques. 9] A newton is larger than a pound.
Indicate whether the statement is true or false
[Ques. 10] If f is the frequency of the emitted radiation, and h is Planck's constant (equal to 6.63 1034 J s), the energy E each emitted quantum of energy has in Planck's explanation of blackbody radiation is:
a. E = h / f.
b. E = h f.
c. E = h + f.
d. E = mc2.
e. E = f / h.
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