Download Chapter 16: Electric Charge and Fields

Chapters 16&17
Sample quiz
1.
Why is static electricity so much more noticeable on days with low relative humidity?
2.
Why is a metal a good conductor?
3.
Describe the process of charging an object by induction.
4.
Contrast the above with charging an object by conduction.
5.
What does it mean when we say "electric charge is quantized"?
6.
Two positive point charges Q1 = 50 C and Q2 = 1C are separated by a distance d. Which is larger
in magnitude, the force that Q1 exerts on Q2 or the force that Q2 exerts on Q1 ?
7.
Electric field intensity is force per unit charge. Electric potential is _________ per unit _______.
8.
We say that a positively charged plate is at a (higher or lower) potential than a negatively charge
plate.
9.
An equipotential surface is (perpendicular or parallel) to an electric field.
10.
A parallel plate capacitor is connected to a battery. If a dielectric is then inserted between the plates
will the stored charge increase or decrease?
Chapters 16&17
True of False?
Sample Quiz
11.
Between two closely spaced oppositely charged parallel plates the electric field is constant.
12.
The electric field points in the direction perpendicular to the electric field lines at any point.
13.
The electric field inside a good conductor is zero.
14.
The electric field is always parallel to the surface outside a conductor.
15.
A relatively safe place to be during a lightning storm is inside a car, surrounded by the metal body.
16.
1 N/C = 1 V/m
17.
No work is required to move a charge from one point to another on an equipotential surface.
18.
The surface of an insulator is always an equipotential surface.
19.
The farad is equivalent to a coulomb / volt.
20. In regions of space where the electric field E is zero, the electric potential V must also be zero.
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Problems I, II, III: Charge Q1 = +3 C is 90 cm to the left of charge Q2 = +6 C.
I.
What force does Q1 exert on Q2 (Magnitude and direction)?
II.
Where on the line connecting the charges does the electric field E equal zero?
III.
Find the electric potential V at the point midway between the charges.
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Chapters 16&17
Sample Quiz
IV. A parallel plate capacitor has plates 40 cm long by 3 cm wide. The plates are separated by an air
gap of 1 mm. The plates are connected to a 12 volt battery.
a.
Calculate the capacitance.
b.
Find the charge on each plate.
c.
Find the electric field intensity (magnitude and direction) between the plates.
d.
Find the energy stored in the electric field.
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