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Two forces with magnitudes of 120 and 70 pounds act on an object at angles of 60 degrees and 150 degrees, respectively. Find the direction and magnitude of the resultant force. Round to two decimal places in your final answer.

1 Answer

2 votes
resolving horizontally . Make forces to the right positive
resultant force = 70cos30-60cos60 = 60.62-60 = 0.62 lbs

resolve vertically
resultant force = 120 sin60 - 70 sin30 = 103.92 - 35 = 68.92 lbs in downward direction

magnitude of the ressultant forsse = sqrt(68.92^2 + 0.62^2) = 68.92 lbs

direction of the force = tan-1 (0.62 / 68.82) = 0.52 degrees east of south or
a bearing of
90 - 0.52 = 89.48 degrees

User Hanh Le
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