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9 |
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An
electron has a mass and a charge . How much work is done by an electric field,
which moves the electron Starting from rest over a distance of 0.300
m through a potential difference of ? |
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So the Correct Answer is B ! |
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10 |
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A
rail gun uses an electric potential difference to launch charged
objects. Consider using this to launch
a satellite into orbit about the Earth.
The mass of a smaller satellite is . It needs to reach geosynchronous orbit,
which is above sea level. Let us assume the satellite can have on it without damaging the satellite. What is the potential difference required
to accelerate the satellite to launch it for this orbit? Is the ground the low or high potential
point? Ignore air resistance! |
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Since the satellite is positively
charged, the ground must be positive compared to the end of the potential
difference to push the satellite up! |
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So Correct answer is D ! |
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11 |
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Suppose
you could transfer the kinetic energy of a car (mass ) travelling at
a speed to an onboard capacitor.
What would the potential difference be across the capacitor if all the
energy were transferred? |
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Solve for V |
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So Correct Answer is C ! |
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12 |
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A
parallel plate capacitor has a dielectric slab with in between the plates. The capacitance of the capacitor with the
dielectric inserted is . The capacitor is fully charged by a 12.0 V
power source and then the power supply is disconnected. The dielectric slab is then removed. What is the change in the potential
difference across the plates of the capacitor? |
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Since the battery is removed, charge
is constant on the plates. |
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And we know |
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so |
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and |
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The change in potential is |
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So Correct Answer is A ! |
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