Answer:
The sound intensity that the other student measure, I₂ is expected to be;
A) 6.2 × 10⁻⁸ W/m²
Explanation:
The measure of sound intensity is given by the following formula;
Where;
I = The intensity
R = The radius
P = The power of the sound
Whereby we have;
The distance of the two people talking, R₁ = 3.0 m
The measure of the sound intensity, I₁ = 1.1 × 10⁻⁷ W/m² (from an online source)
The distance of the other student from the two people talking, R₂ = 4.0 m
Therefore, the estimate of the sound intensity, I₂, is given as follows;
I₂ = 6.1875 × 10⁻⁸ W/m²
∴ The sound intensity that the other student measure, I₂ ≈ 6.2 × 10⁻⁸ W/m²
Answer:
0.017 N
Explanation:
The relevant relation is ...
F = GMm/r²
where G is the universal gravitational constant, 6.67408 × 10^-11 m^3·kg^-1·s^-2, M and m are the masses of the objects, and r is the distance between them.
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Filling in the given numbers, we find the force to be ...
F = (6.67408 × 10^-11 m^3·kg^-1·s^-2)(8.7 × 10^20 kg)(77 kg)/(1.6 × 10^7 m)^2
where m in this expression is the unit "meters".
F = 6.67408 · 8.7 · 77/2.56 × 10^(-11 +20 -2·7) N ≈ 0.017 N
The asteroid exerts a force of about 0.017 N on Sally.
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<em>Additional comment</em>
That's about 0.000023 times the force of Earth's gravity.
All the colors of the visible spectrum
The formula for speed is s = d/t, where s is speed, d is distance, and t is time. The formula can be applied to all objects, including cars, to find their speed.