A proton beam that carries a total current of 1.3 mA has 10.0 mm diameter. The current density in the proton beam increases linearly with distance from the center
This is expressed mathematically as J(r) = J0 (r/R), where R is the radius of the beam and J0 is the current density at the edge. Determine the value of J0. A) 25 A/m2
B) 6.2 A/m2
C) 12 A/m2
D) 17 A/m2
A
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If body P, with a positive charge, is placed in contact with body Q (initially uncharged), what will be the nature of the charge left on Q?
a. must be equal in magnitude to that on P b. must be negative c. must be positive d. must be greater in magnitude than that on P
Which of the following statements about degeneracy pressure is not true?
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Which of these statements about Hubble's classification scheme for galaxies is false?
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The easiest way to remember which quarks make up a neutron is
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