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1.
(1 point)
What is the net static electric charge on a metal sphere having an excess of +3 elementary charges?





2.
(1 point)
A hydrogen atom could have an electron energy level transition from n=2 to n=3 by absorbing a photon having an energy of?





3.
(1 point)
Two solid metal blocks are placed in an insulated container. If there is a net flow of heat between the blocks, they must have different?





4.
(1 point)
A (P type) semiconductor is formed by adding impurities, which provide extra ____.





5.
(1 point)
A student measures a current of .05 ampere through a P type semiconductor. If the battery connections are reversed, the current through the semiconductor will be?




6.
(1 point)
What is the approximate bind energy of a helium nucleus that has a mass defect of 5.2 x 10-29 kilogram?





7.
(1 point)
Which particle cannot be accelerated by a cyclotron?





8.
(1 point)
A 96 gram sample of a radioactive nuclide is placed in a container. After 12 minutes only 6 grams of the sample has not yet decayed. What is the half life of the nuclide?





9.
(1 point)
The principal reason for using neutrons to bombard a nucleus is that neutrons?





10.
(1 point)
What is the magnitude of the gravitational force between an electron and a proton separated by a distance of 1.0 x 10-10 meter?





11.
(1 point)
A sphere has a net excess charge of –4.8 x 10-19 coulomb. The sphere must have an excess of ______.





12.
(1 point)
An excited hydrogen atom returns to its ground state. A possible energy change for the atom is?





13.
(1 point)
During a collision between a proton and an electron there is conservation of _____.





14.
(1 point)
As the temperature of a surface increases, how does the rate of thermionic emission change?






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