Click on a question number!






































1.
In the Rutherford scattering experiment, the "targets" were

electrons
gold atoms
X-ray photons
beta particles






































2.
Why was Rutherford so surprised at the results of his scattering experiment?

Answer





































3.

Choose all correct options below (unless all are incorrect):

Quanta (a.k.a. photons)

(For multiple selections, press "Ctrl" while clicking.)







































4.
A hot incandescent object emits ________ light than does a cool one of the same size.

(You can check 0, 1, or 2 boxes before submitting.)

brighter
shorter-wavelength







































5.
In the photoelectric effect experiment, the stopping voltage tells us

the charge of the photoelectrons
the number of photoelectrons ejected per second
the mass of the photons
the kinetic energy of the photoelectrons






































6.
Why was it considered strange that low-frequency light, no matter how bright, couldn't produce any photocurrent when shined on a metal plate?

Answer





































7.

Choose all correct options below (unless all are incorrect):

You can increase the kinetic energy of electrons ejected from a metal plate by shining _____ light on the plate.

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8.
Which of the following has the least energetic photons?

green
ultraviolet
infrared
X-rays






































9.
UV light consisting of 4.8 eV photons is shined on metal, producing photoelectrons whose maximum kinetic energy is 1.9 eV.  If we now switch to violet light consisting of 3.1 eV photons, what is the maximum electron kinetic energy?







































10.
How was J. J. Thomson able to measure the charge-to-mass ratio (e/m) of the electrons he discovered?

Answer





































11.
An example of Brownian motion would be the random motion of a _______ in water.

fish
water molecule
pollen grain
beach ball






































12.
How does Brownian motion demonstrate the reality of atoms?

Answer





































13.
J. J. Thomson was able to measure the ________ of the electrons he discovered.

(You can check 0, 1, or 2 boxes before submitting.)

charge
mass







































14.
Max Planck claimed that the atoms in the walls of a blackbody