Four coplanar forces act at a point. The magnitudes of the forces are 5N, 4N, 3N and 7N, and the
directions in which the forces act are shown in the diagram. Find the magnitude and direction of the
resultant of the four forces.

Question

Four coplanar forces act at a point. The magnitudes of the forces are 5N, 4N, 3N and 7N, and the
directions in which the forces act are shown in the diagram. Find the magnitude and direction of the
resultant of the four forces.

abmon98 · Answer

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abmon98 · Answer

Horizontal x-component 5-7cos60-3cos30
Vertical y-component 7sin60-3sin30-4

mrnood · Answer

OK - so you have done the main part of the work.

Once you have calculated those 2 resultant components (X & Y) you can combine them to get the overall resultant.

You combine them by using Pythagoras fro the magnitude of the force:
The resultant is the hypotenuse of the triangle made by the two components
(x^2 + y^2 = r^2)
The direction is got by Theta= tan^-1 (Y/X)

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