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nataly862011 [7]

2 years ago

14

A boy drops a 0.10 kg stone down a 150 m well and listens for the echo. The air temperature is 20°C. How long after the stone is

dropped will the boy hear the echo? The speed of sound through air at 20°C is v = 343 m/s.

1 answer:

S_A_V [24]2 years ago

4 0

Use formula for Echo which is Velocity=2(Distance)/time so 343=2(150)/T 343T=300..T=300/343=0.9 seconds

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Bohr's equation for the change in energy is
$\Delta E= \frac{hc}{\lambda}$
where
h = Planck's constant
c == the velocity of light
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The velocity is related to wavelength and frequency, f, by
c = fλ

Let us examine the given answers on the basis of the given equations.

a. As λ increases, f decreases and ΔE decreases.
TRUE

b. As λ increases, f increases and ΔE increases.
FALSE

c. As λ increases, f increases and ΔE decreases.
FALSE

Answer:
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3 years ago

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sergey [27]

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3 years ago

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allsm [11]

Answer:

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Explanation:

From Gauss's Law

Φ = Q/ε₀

where;

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Q is the total charge Q in the shell = ?

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From this equation; Φ = Q/ε₀

Q = Φ * ε₀ = − 533 * 8.85 x 10⁻¹²

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Explanation:

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Answer:

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