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2 個解答
- WhomeLv 73 年前最愛解答
1) the Fg force of mutual attraction between mass and earth.
F = GMm/r²
F = (6.674 x 10^-11)(5.972 × 10^24)(100) / (6.371 x 10^6 + 78000)²
F = 958.34...
F = 960 N
rounded to the two significant digits of the question numerals
2) the acceleration of the earth due to this force.
F = ma
a = F/m
a = 958.34 / 5.972 × 10^24
a = 1.6 x 10^-25 m/s²
which is a very very small acceleration.
If my translation and interpretation of this question is incorrect and it is really asking for the acceleration of the mass due to the earth, then
a = 958.34 / 100
a = 9.6 m/s²
3) the initial velocity Vo with which the object must be fired (frictions excluded)
ac = (Vo)²/r
Vo² = ac(r)
Vo² = 9.58(6.371 x 10^6 + 78000)
Vo² = 61803346.6
Vo = 7861.51...
Vo = 7900 m/s
or
Vo = √(GM/r)
Vo = √((6.674 x 10^-11)(5.972 × 10^24) / (6.371 x 10^6 + 78000))
Vo = 7861.52...
Vo = 7900 m/s
I hope this helps.
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- 匿名3 年前
perché l'utente Giorgio segnala a manetta basta vedere che solo lui è in testa alla classifica con 5,464 è penoso sta qui da solo ad autovotarsi, segnalatelo fino al ban, passate parola