Hello Everyone, I've been trying to get the answer to this problem for ages now and I just can't match my answer with the one in the back of the textbook. I hope you can let me know what I'm doing wrong.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

What is the gravitational field strength at a place 220 km above Earth's surface, the altitude of many piloted space flights.

2. Relevant equations

Fg = mg

Fg = Gm₁m₂/d²

3. The attempt at a solution

d = 6.60 x 10³ km

G = 6.67 x 10-¹¹ N.m²/kg²

m₂ = 5.98 x 10²⁴ kg

g = ? N/kg

Fg = mg = Gm₁m₂/d²

mg/m = Gm₁m₂/d²/m

g = Gm₂/d²

g = (6.67 x 10-¹¹ N.m²/kg²)(5.98 x 10²⁴ kg)/((6.60 x 10³ km)²)

And when I do this I always get the wrong answer when I compare it with the one in the back of the textbook. The answer in the back of the textbook is 9.1 N/kg [down].

If anyone here could please help me with this, that would be great.

Thanks.

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# Homework Help: Gravitational Field Strength Help

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