(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A spaceship lifts off vertically from the Moon, where g = 1.6 m/s2. If the ship has an upward acceleration of 1.0 m/s2 as it lifts off, what is the magnitude of the force exerted by the ship on its pilot, who weighs 735 N on Earth?

From Halliday, Fundamentals of Physics, 9e

2. Relevant equations

Newton's Second Law: F(net)= ma

3. The attempt at a solution

I'm more looking for an explanation on why the answer is 195 N.

Granted I can see that they added the two forces. (75kg*1.0m/s2 + 75kg*1.6m/s2)

What I do not understand is why I need to add the twopositiveforces. I was trying to draw a few body diagram.

What I was picturing: two force vectors in opposite direction. So the magnitude would result in 45N if this were the case.

Thanks in advance.

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# Homework Help: Newtons Second Law: Finding net forces

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