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2 years ago

Karen claps her hand and hears the echo from

Physics

1 answer:

Alinara [238K]2 years ago

3 0

Answer:

89 m

Explanation:

Applying

v = 2d/t................... Equation 1

Where v = velocity of sound in air, d = distance of the wall from Karen, t = time taken to hear the echo.

make d the subject of equation 1

d = vt/2..................... Equation 2

From the question,

Given: v = 343 m/s, t = 0.519 s

Substitute these values into equation 2

d = (343×0.519)/2

d = 89.01 m.

d ≈ 89 m

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$F=k\frac{q_1 q_2}{r^2}$ (1)

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r is the separation between the charges

When the two spheres are brought in contact with each other, the charge equally redistribute among the two spheres, such that each sphere will have a charge of

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So, the final charge on the sphere on the right is

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Now we know the total charge initially on the two spheres. Moreover, at the beginning we know that

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And also,

$q_2 = Q-q_1$

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$F=k \frac{q_1 (Q-q_1)}{r^2}$

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which gives two solutions:

$q_1 = 6.70\cdot 10^{-6} C\\q_2 = -2.34\cdot 10^{-6} C$

Which correspond to the values of the two charges. Therefore, the initial charge q1 on the first sphere is

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