The earth's gravitational field intensity at its surface is about
(G = 6.7 × 10\(^{-11}\)Nm\(^2\)/kg\(^2\), mass of the earth is 6 × 10\(^{24}\)kg, radius of the earth is 6.4 × 10\(^6\)m, g on the earth = 9.8m/s\(^2\))

A.

6.7N/kg

B.

7.9N/kg

C.

8.0N/kg

D.

9.8N/kg

Correct answer is D

E = F
m
= GMm/d\(^2\)
m
= GM
d\(^2\)

 

E = 6.7 × 10\(^{-11}\) × 6 × 10\(^{24}\)
(6.4 × 10\(^6\))\(^2\)
= 9.8N
kg


E = g = 9.8N/kg