Area near a sea having flat land and low relief
Answer:
16km/h
Explanation:
Vt=20km/h ---train speed
Vd=4km/h
Donas speed relative to ground is:
Vrd=Vt-Vd
Donas is moving in opposite direction of train .
Vrd=20km/h-4km/h
Vrd=16km/h
We have that the magnitude of the gravitational force is mathematically given as
f=6.377N
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Force</h3>
Question Parameters:
Earth exerts a 100 N gravitational force on a metal box.
(Mass of the earth is 6e24 kg and radius of the earth is 6.4e6m.)
Generally the equation for the Gravitational mForce is mathematically given as

f=6.377N
For more information on Force visit
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