Question

A body of mass 40 kg has weight 460 N at a certain planet. What is the weight of: (a) 450 gr (b) 50 kg and (c) 15 gr on that planet?

Answer 1

The weights are: a) `5.175 N`, b) `575 N` and c) `0.1725 N`

Explanation:

The mass and weight are used to determine the strength of the gravitational field `g` on the planet as follows:

`g=W/m = (460 N)/(40 kg) = 11.5 N/(kg)`

This means that the planets gravity will cause any `1 kg` of mass to register a weight of `11.5 N`. So,

`W=mg`

tells us that the other bodies weigh:

a) `0.45 kg xx 11.5 N/(kg) = 5.175 N`

b) `50 kg xx11.5 N/(kg) = 575 N`

c) `0.015 kg xx 11.5 N/(kg) = 0.1725 N`