Transcript Electrostatics Review

Electrostatics Review
LCHS
Dr.E
Which is a vector quantity?
(A) speed
(B) work
(C) mass
(D) displacement
Which object has the greatest inertia?
(A) a 5.00-kg mass moving at 10.0 m/s
(B) a 10.0-kg mass moving at 1.00 m/s
(C) a 15.0-kg mass moving at 10.0 m/s
(D) a 20.0-kg mass moving at 1.00 m/s
A positive test charge is placed between an
electron, e, and a proton, p, as shown in the
diagram below.
When the test charge is released, it will move
toward
(A) A
(B) B
(C) C
(D) D
In an electric field, 0.90 joule of work is
required to bring 0.45 coulomb of charge
from point A to point B. What is the
electric potential difference between
points A and B?
(A) 5.0 V
(B) 2.0 V
(C) 0.50 V
(D) 0.41 V
In the diagram above, proton p, neutron n, and electron
e are located as shown between two oppositely charged
plates. The magnitude of acceleration will be greatest
for the
(A) neutron, because it has the greatest mass
(B) neutron, because it is neutral
(C) electron, because it has the smallest mass
(D) proton, because it is farthest from negative plate
Two protons are located one meter
apart. Compared to the gravitational
force of attraction between the two
protons, the electrostatic force between
the protons is
(A) stronger and repulsive
(B) weaker and repulsive
(C) stronger and attractive
(D) weaker and attractive
A balloon is rubbed against a student’s hair and then
touched to a wall. The balloon “sticks” to the wall
due to
(A) electrostatic forces between the particles of the
balloon
(B) magnetic forces between the particles of the
wall
(C) electrostatic forces between the particles of the
balloon and the particles of the wall
(D) magnetic forces between the particles of the
balloon and the particles of the wall
Two positively charged masses are
separated by a distance, r. Which statement
best describes the gravitational and
electrostatic forces between the two masses?
(A) Both forces are attractive.
(B) Both forces are repulsive.
(C) The gravitational force is repulsive and the
electrostatic force is attractive.
(D) The gravitational force is attractive and
the electrostatic force is repulsive.
A distance of 1.0 meter separates the centers of two
small charged spheres. The spheres exert
gravitational force Fg and electrostatic force Fe on
each other. If the distance between the spheres’
centers is increased to 3.0 meters, the gravitational
force and electrostatic force, respectively, may be
represented as
(A) Fg and Fe
9
9
(B) 3Fg and 3Fe
(C) Fg and Fe
3
3
(D) 9Fg and 9Fe
A beam of electrons is directed into the electric
field between two oppositely charged parallel
plates. The electrostatic force exerted on the
electrons by the electric field is directed
(A) into the screen
(B) out of the screen
(C) toward the bottom of the screen
(D) toward the top of the screen
The particles in a nucleus primarily by
the are held together
(A) magnetic force
(B) gravitational force
(C) electrostatic force
(D) strong force
A charge of 30 coulombs passes through
a 24-ohm resistor in 6.0 seconds. What is
the current through the resistor?
(A) 1.3 A
(B) 5.0 A
(C) 7.5 A
(D) 4.0 A
The diagram represents the
electric field surrounding
two charged spheres,
A and B. What is the sign of the charge of each
sphere?
(A) Sphere A is positive and sphere B is
negative.
(B) Sphere A is negative and sphere B is
positive.
(C) Both spheres are positive.
(D) Both spheres are negative.
The centers of two small charged
particles are separated by a distance of
1.2 × 10–4 meter. The charges on the
particles are +8.0 × 10–19 Coulomb and
–19
+4.8 × 10 Coulomb, respectively.
Calculate the magnitude of the
electrostatic force between these two
particles.
A potential difference of 10.0 volts exists
between two points, A and B, within an
electric field. What is the magnitude of
–2
charge that requires 2.0 × 10 joule of
work to move it from A to B?
(A) 5.0×102 C
(B) 2.0×10–1 C
(C) 5.0×10–2 C
(D) 2.0×10–3 C
Two small identical metal spheres, A and
B, on insulated stands, are each given a
–6
charge of +2.0 × 10 Coulomb. The
–1
distance between the spheres is 2.0 × 10
meter.
Calculate the magnitude of the
electrostatic force that the charge on
sphere A exerts on the charge on sphere B.
The diagram below represents an electron
within an electric field between two parallel
plates that are charged with a potential
difference of 40.0 volts. If the magnitude of the
electric force on the electron is 2.00 × 10–15
newton, the magnitude of the electric field
strength between the charged plates is
(A) 3.20 × 10–34 N/C (B) 2.00 × 10–14 N/C
(C) 1.25 × 104 N/C
(D) 2.00 × 1016 N/C
Two small metallic
spheres, A and B,
are separated by a
distance of 4.0 × 10–1
meter, as shown. The charge on each sphere is
+1.0 × 10–6 coulomb. Point P is located near
the spheres. What is the magnitude of the
electrostatic force between the two charged
spheres?
(A) 2.2×10–2 N (B) 5.6x10–2 N
(C) 2.2×104 N (D) 5.6×104 N
An electroscope is a device with
a metal knob, a metal stem, and
freely hanging metal leaves used
to detect charges. The diagram shows a
positively charged leaf electroscope. As a
positively charged glass rod is brought near the
knob of the electroscope, the separation of the
electroscope leaves will
(A) decrease
(B) increase
(C) remain the same
Compared to insulators, metals
are better conductors of electricity
because metals contain more free
(A) protons
(B) positive ions
(C) electrons
(D) negative ions
Electrostatic force F exists between
two point charges. If the distance
between the charges is tripled, the
force between the charges will be
(A) F/9
(B) 3F
(C) F/3
(D) 9F
How much work is done in moving
5.0 coulombs of charge against a
potential difference of 12 volts?
(A) 2.4 J
(B) 30. J
(C) 12 J
(D) 60. J
How much work is required to
move a single electron through a
potential difference of 100. volts?
(1) 1.6 ×
–17
(3) 1.6 × 10 J
–19
(2) 1.6 × 10 J
2
(4) 1.0 × 10 J
–21
10 J
Metal sphere A has a charge of +12
elementary charges and identical sphere B
has a charge of +16 elementary charges.
After the two spheres are brought into
contact, the charge on sphere A is
(A) –2 elementary charges
(B) +2 elementary charges
(C) +14 elementary charges
(D) +28 elementary charges
What is the approximate electrostatic
force between two protons separated by
–6
a distance of 1.0 ⋅ 10 meter?
(1) 2.3 ⋅
N and repulsive
(2) 2.3 ⋅ 10–16 N and attractive
(3) 9.0 ⋅ 1021 N and repulsive
(4) 9.0 ⋅ 1021 N and attractive
–16
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