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Demonstrate how you can derive our 9.8m/s^2 from Newton's general law of gravity.

1 Answer

11 votes

Answer:


g=G(m_E)/(r^2)

Step-by-step explanation:

Using Newton's Law of Universal Gravitation, we can write:


F=G(m_E)/(r^2), where
G is gravitational constant
6.67\cdot 10^(-11),
m_E is Earth's mass, and
r is Earth's radius.

Using these measured values, we have:


F=6.67\cdot 10^(-11)(5.97\cdot 10^(24))/((6.38\cdot10^6)^2),\\g\approx \fbox{$9.8\:\mathrm{m/s^2}$}.