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3 years ago

14

A capacitor of capacitance C has charge Q and stored energy is U if the charge is increased to 2Q then energy will be A)4U B)2U

C)U/2 D)U/4

1 answer:

Lubov Fominskaja [6]3 years ago

8 0

Answer:

2u

Explanation:

2u

W = Vq

q = CV

W = V.CV

W = CV²

W/C = V²

V = √(W/C)

√(W1/C1) = √(W2/C2)

√(u/c) = √(x/2c)

x = 2u

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Answer:

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pf = (n m + M) v

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n m (v₀ - v) = M v

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Let's look for the initial velocity of the balls, suppose the person throws them with the maximum force if it slides in the snow (F = 100N), let's use the second law and Newton

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Answer:

a. 2.668 m/s

b. 0.00494

Explanation:

The computation is shown below:

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We know that

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The energy following 100 meters equivalent to the initial kinetic energy less the energy lost to the work performed by the wind on the skater.

So, the equation is

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Now solve for v2

$v2 = \sqrt{v1^2 - {\frac{2W}{M}}}$

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As we know that

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