a 1.5-kg object moves up the y-axis at a constant speed. When it reaches the origin,the forces F1 =5.0 N at 37 deg above the the + x-axis, F2 = 2.5 N in the +x-direction, F3 = 3.5 N at 45 deg below the -x-axis, and F4 = 1.5 N in the -y direction are applied to it(a) Will the object continue to move along the y-axis? (b) If not, what simultaneously applied force will keep it moving along the y-axis at a constant speed?

Question

a 1.5-kg object moves up the y-axis at a constant speed. When it reaches the origin,the forces F1 =5.0 N at 37 deg above the the + x-axis, F2 = 2.5 N in  the +x-direction, F3 = 3.5 N at 45 deg below the -x-axis, and F4 = 1.5 N in the -y direction are applied to it(a) Will the object continue to move along the y-axis? (b) If not, what simultaneously applied force will keep it moving along the y-axis at a constant speed?

drwls · Answer

(a) Add up the four forces as vectors and see if there is an net x component in the resultant vector. If there is, the motion will deviate from the y axis.

(b) The answer is called the "equilibrant" and is equal to the negative of the resultant vector you got in (a). It has the same magnitude as the resultant but s in the opposite direction.