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Los Altos Physics Electrostatics Workbook
Los Altos Physics
Electrostatics
ultiple ionisationhighly charged ions
Electric Field Hockey
Mr. Randall - Room 705
Spring 2013www.LAPhvsics.com
Los Altos Physics Electrostatics Workbook
1. Consider two protons; one at rest on the surface of the Earth, the other sitting inequilibrium directly above the first. How far above the first proton is the second proton?
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Los Altos Physics Electrostatics Workbook
Suppose that electrical attraction, rather than gravity were responsible for holding themoon in orbit around the Earth. If equal and opposite charges Q were placed on theEarth and the Moon, what should be the value of Q to maintain the present orbit?(Hint: treat the Earth and moon as point particles.)
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Consider two charges separated by a distance r. If the separation distance isincreased to 3r and the magnitude of one charge is reduced by Vz, predict how manytimes smaller the new electrostatic force between them would be?
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Los Altos Physics Electrostatics Workbook
4. Consider two samples of protons each with 1.00 Kg of mass separated by 1.00 m.
A. Predict the magnitude of the gravitational force between the two .B. Predict the magnitude of the electrical force between the two.C. Calculate the ratio of electric force to gravitational force. What does this ratio
represent in terms of the stronger force?
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Los Altos Physics Electrostatics Workbook
Consider an electron with an initial velocity of 1.40 x 103 m/s entering a parallel platecapacitor. The capacitor's plates are separated by a distance of 3.50 cm. Predict thestrength of the electric field that will stop the electron just before it reaches the bottomplate.
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Los Altos Physics Electrostatics Workbook
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Consider an positive, singularly ionized water molecule at rest, hovering at rest, insidea parallel plate capacitor near the surface of the Earth. _i -
Predict the direction of the electric field inside the capacitor.
Predict the magnitude of the electric field inside the capacitor.
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Los Altos Physics Electrostatics Workbook
7. Consider an alpha particle (Helium Nuclei = 2 Protons + 2 Neutrons) shot out of aparticle canon with an initial velocity of 2.30 x 103 m/s @ 30.0° into an electric field of3.00 x 103 N/C directed downward. Predict the range and final velocity of the alphaparticle if it's change in vertical displacement is zero. Ignore the effects of gravity.
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