Three astronauts equipped with jetpacks

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Three astronauts are using jetpacks to push a 121 kg satellite in space, applying various forces at different angles. The net forces in the x and y directions were calculated, resulting in Fnet x of approximately 101.84 N and Fnet y of about -18.33 N. The total net force was determined to be -103.47 N, leading to an acceleration calculation using Fnet = ma. The final acceleration was found to be -0.85 m/s², but clarification was needed regarding the use of the negative sign for magnitude. It was confirmed that magnitudes should be unsigned, resolving the confusion.
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Three astronauts equipped with jetpacks are pushing a satellite, having a mass of 121kg, through space. The forces being exerted on the satellite are F1=31.8N at an angle of 31.0 degrees above the horizontal (θ1), F2=40.0N at 60.2 degrees below the horizontal (θ2), and F3=54.7N along the horizontal.

What is the magnitude of the satellite's acceleration?

So I tried to solve it by adding all the FnetX, and Fnet Y

Fnet x= 31.8 cos 31 + 54.7 + 40.0 cos 60.2
= 27.2579 + 54.7 + 19.8789584
= 101.8368786 N

Fnet y= 31.8 sin 31 - 40.0 sin 60.2
= 16.37821 - 34.71061813
= -18.332408 N

tan θ = 101.8368786 / -18.332408
θ = -79.79506177

sin θ = Fnet x/ Fnet
sin (-79.79506177) = 101.8368786/ Fnet
Fnet = -103.47 N

Fnet = ma
a = Fnet/m
a = -103.4737987 N/121 kg
a = -0.85 m/s^2

But apparently it's wrong, can someone help please?
 
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p14r said:
Fnet = ma
a = Fnet/m
a = -103.4737987 N/121 kg
a = -0.85 m/s^2

But apparently it's wrong, can someone help please?
Did you include the minus sign in your answer? They wanted the magnitude of the acceleration.
 
Yup i did, so i shouldn't enter the negative sign?
 
p14r said:
Yup i did, so i shouldn't enter the negative sign?
No you shouldn't. Magnitudes are unsigned.
 
It worked, thank you so much!
 
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