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# Physics/Physics-Acceleration due to Gravity

Question
Hi,just wondering if you could help me with this question please.

An object of mass 4.9kg is pulled along a smooth horizontal table by means of 2 forces. One of the forces = 37N along the x-axis(horizontal) and the other force =32N along the y-axis which is also horizontal. *Note-the acceleration due to gravity(g) id 9.8ms^-2.
What is the acceleration of the object?
...
I'm just a bit confused. I'm pretty sure the correct equation to use is ga=GM/r^2 but I don't know how to find r,the radius?

ga =GM/r^2 will calculate the acceleration due to gravity at the surface of the Earth if you put in the Earth's mass and radius.  You don't need that here.
You have two forces at right angles so the net force = (32^2+37^2)^1/2 = 48.9N
So you have F = ma, 48.9 = 4.9a and a = 9.98m/s^2
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#### Richard J. Raridon

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