Answer:
W ’= 21.78 kg
Step-by-step explanation:
The expression for weight is
W = m g
let's look for the acceleration of gravity with the universal law of gravitation
F = G m M / r2
F = m (G M / r2)
without comparing the two equations
g’= G M / r2
in that case M = 2 Mo and r = 3 ro
where mo and ro are the mass and radius of the earth
we substitute
g ’= G 2Mo / (3r₀) 2
G ’= 2/9 G Mo / r₀²
g ’= 2/9 g
the weight of the body on this planet is
W ’= m g’
W ’= m 2/9 g
let's calculate
W ’= 2/9 10 9.8
W ’= 21.78 kg