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hodyreva [135]
3 years ago
5

Suppose that we have a 1000pF parallel-plate capacitor with air dielectric charged to 1000V. The capacitor terminals are open ci

rcuited.
Find the stored energy. If the plates are moved farther apart so that d is doubled, determine the new voltage on the capacitor and the new stored energy.

Where did the extra energy come from?

Please show all workings & calculations on how you came to your answer.
Engineering
1 answer:
N76 [4]3 years ago
4 0

Answer:

W = 1 mJ

V_new = 2000 V

W_new = 2 mJ

The extra energy came from the work done from moving the plates

Explanation:

We are given;

Capacitance; C = 1000pF = 10^(-9) F

Voltage; V = 1000V

Now,formula for stored energy in a parallel plate capacitor is given by;

W = (1/2)CV² = (1/2)(10^(-9))(1000²) = 0.5 mJ

However, in this case, it's W = 0.5 x 2 = 1 mJ since parallel-plate capacitor with air dielectric

When plates are moved and distance between plates is doubled(net charge is the same), thus we can calculate voltage from;

Q = CV

Since, C_new = C/2

Thus,

Q = (C/2)V_new

V_new = 2Q/C

Thus, V_new = 2V

Thus, V_new = 2 x 1000 = 2000 V

Now,

W_new = (1/2)C_new•(V_new)² = (1/2) (0.5C)•(2V)² = CV² = 2W = 2 x 1 = 2mJ

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Explanation:

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\omega _{beam}=\sqrt{\frac{\frac{3\times 20.5\times 10^{10}\times \frac{0.1\times 0.3^3}{12}}{5.9^{3}}}{0.3\times 0.1 \times 7830}}=53.56rad/sec

8 0
3 years ago
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SB-4 Which one of the following is true about red buoys under the U.S. Aids to Navigation System?
stich3 [128]

Question:

1. Some are known as "nun" buoys

2. They are labeled with odd numbers

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4. Some are known as "can" buoys

Answer:

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1. Some are known as "nun" buoys

Explanation:

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g Consider a thin opaque, horizontal plate with an electrical heater on its backside. The front end is exposed to ambient air th
xxTIMURxx [149]

Answer:

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svetlana [45]

Answer:

oof

Explanation:

I don't know but please don't report me

I am trying to do a challenge

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If you don't report me!

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