Physics 121 Practice Problem Solutions 02 Electric Charge

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Physics 121 Practice Problem Solutions 02
Electric Charge
Contents
121P02 -1P, 2P, 5P, 9P, 10P, 13P, 15P

• History
• Electromagnetism
• Electric Charge
• Quantization of Charge
• Structure of Matter
• Conductors and Insulators
• Conservation of Charge
• Coulombs Law Force
• Shell Theorem
• Examples

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PROBLEM 121P02- 1P What must be the distance
between point charge q1 26.0 mC and point
charge q2 -47.0 mC for the electrostatic force
between them to have a magnitude of 5.70 N?
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PROBLEM 121P02 - 2P A point charge of 3.00 x
10-6 C is 12.0 cm distant from a second point
charge of -1.50 x 10-6 C. Calculate the
magnitude of the force on each charge.
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PROBLEM 121P02 - 5P In the figure , what are the
(a) horizontal and (b) vertical components of the
net electrostatic force on the charged particle
in the lower left corner of the square if q
1.0x10-7 C and a 5.0 cm?
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(No Transcript)
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PROBLEM 121P02 - 10P Two fixed particles, of
charges q1 1.0 mC and q2 -3.0 mC, are 10 cm
apart. How far from each should a third charge be
located so that no net electrostatic force acts
on it?
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PROBLEM 121P02 - 13P A certain charge Q is
divided into two parts q and Q - q, which are
then separated by a certain distance. What must q
be in terms of Q to maximize the electrostatic
repulsion between the two charges?
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PROBLEM 121P02 - 15P In the figure, two tiny
conducting balls of identical mass m and
identical charge q hang from nonconducting
threads of length L. Assume that q is so small
that tan q can be replaced by its approximate
equal, sin q. (a) Show that, for equilibrium,
where x is the separation between the balls.
(b) If L 120 cm, m 10 g, and x 5.0 cm, what
is q?