Can anyone provide a step by step explanation?

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1 Answer
Mar 28, 2016

(a) 0.284ms2 rounded to three decimal places.
(b) 17.89N rounded to two decimal places
(c) 3.8s rounded to one decimal place.

Explanation:

As per Law of Universal Gravitation the force of attraction between two bodies is directly proportional to the product of masses of the two bodies. it is also inversely proportional to the square of the distance between the two.
Mathematically
FGM1.M2
Also FG1r2
Combining the two we obtain the proportionality expression

FGM1.M2r2

FG=GM1.M2r2
Where G is the proportionality constant.
and has a value =6.67408×1011m3kg1s2

If one of the bodies is Ceres, and the other body of mass mthe force equation becomes
FCeres=GMCeres.mr2Ceres
Comparing with the well known equation F=m×aorWeight=m×g
(1) Acceleration due to gravity on the surface of Ceres
g=GMCeresr2Ceres, plug in given values
g=6.67408×10119.4×1020(4.7×105)2
g=0.284ms2 rounded to three decimal places.
(2) Weight of 63kg person on the surface of Ceres=63×0.284
=17.89N rounded to two decimal places
(c) We have the following equation for free fall under gravity

h=ut+12gt2, plug in known values
2=0×t+12×0.284×t2, solving for t
t2=2×20.284
t=3.8s rounded to one decimal place.