Posted by **sarah** on Tuesday, January 8, 2013 at 11:25pm.

three forces with magnitudes 100, 50, and 80 lb act on an object at angles of 50 degree, 160 degree, and -20 degree respectively. ind the direction and magnitude o the resultant force.

- calculus -
**Reiny**, Tuesday, January 8, 2013 at 11:49pm
express each as a vector in component form

magnitude 100,direction 50

= (100cos50, 100sin50) = (64.279 , 76.604)

mag50,direction160

= (-8.682 , 17.101

mag80, direction -20

= ( 75.175 , -27.361)

add up the 3 vectors

= (130.772 , 66.344)

magnitude = √(x^2 + y^2) = 146.638

direction :

tan Ø = 66.344/130.772

Ø = 26.9° or 333.1°

but my sketch showed the resultant to be in the first quadrant, so

Ø = 26.9°

- calculus -
**Steve**, Wednesday, January 9, 2013 at 10:39am
mag50,direction160 = (-46.985,17.101)

## Answer this Question

## Related Questions

- pre-cal - Three forces with magnitudxes 100, 50 and 80 lbs act on an object at ...
- Pre Cal - Two forces with magnitudes of 100 and 50 pounds act on an object at ...
- Calculus - Three forces with magnitudes 75 pound, 100 lb, and 125 pound act on ...
- Calculus help! - Three forces with magnitudes 75 pound, 100 lb, and 125 pound ...
- physics - a body is under of 2 forces 7n and 10n find the resultant of 2 forces ...
- physics - a body is under of 2 forces 7n and 10n find the resultant of 2 forces ...
- physics - two forces f1 and f2 are acting at a point such that the angles ...
- physics - two forces f1 and f2 are acting at a point such that the angles ...
- PHYSICS - the sum of the magnitude of two forces acting at a point is 18 and the...
- physics - three forces, each of magnitude 1450 LB act in the same point. The ...