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.
Well, your muscles are made of of the two (most important) filaments. When one of them moves over the other <span>filaments, the muscles is contracted. If there is an answer choice, I may be able to provide you with a more accurate answer, if this did not already help. ;)</span>
Answer:
Most of the oxygen in the atmosphere is in the form of O2, which means it is made up of molecules containing two oxygen atoms. Ozone, however is O3, which means it is made up of molecules containing three oxygen atoms. O2 is what we breath, and what plants release from photosynthesis. Ozone occurs naturally high in the stratosphere, where it absorbs ultraviolet light, protecting us here on the surface from skin cancer. Ozone can also occur closer to the surface of the earth as a pollutant. It is formed from reactions with O2 and chemicals emitted from factories and cars. It comes in the form of smog.
So in general:
Oxygen (O2): Essential to human life
Ozone (O3) in the stratosphere: essential to protecting life on earth
Ozone (O3) on the surface of the earth: toxic to human life, caused by pollution
