Question

Find the resultant of two forces, one of 72 pounds and the other of 56 pounds, if they act at a point at an angle of 37 degrees.

show work please!
choices :
43 lb.
108 lb.
121 lb.

Answer 1

The resultant of two forces is 43 lb.

Explanation:

First force (
`F_(1)`)= 72 pound

Second force (
`F_(2)`)= 56 pound

Angle between two force (α) = 37°

Now using the relation as:

Resultant force (R²) =
`F_(1)`² +
`F_(2)`² - 2×
`F_(1)` ×
`F_(2)` × Cosα

or, R² = 72² + 56² - 2× 72× 56× Cos(37)

or, R²= 8320 - 8064× 0.798

or, R=
`√(1884.9)`

∴ R= 43 lb

Hence the resultant of two forces is 43lb.