Two forces acting on an object produce the minimum net force if they are acting at an angle of:Multiple Choice: a) 0 degrees b) 45 degrees c) 90...

We have to deal with the additional vectorial structure called an inner product. In  this type of additional structure  each pair of vectors in the space is associated with a scalar quantity, called the inner product of the vectors.

In this case, the 2 forces are the 2 vectors above and if the 2 vectors are on the same dirrection but  the opposite sense, the angle between 2 forces will be 180degrees, so the minimum force will be reached at 180 degrees.

Explanation:

The inner product of the resultant force is

F1*F2=IF1I*IF2I*cos (F1,F2)

Wr know that the minimum value of the 

IF1I*IF2I*cos (F1,F2) is given by the minimum value of the cos (F1,F2)=-1 when the angle between F1 and F2 is 180degrees, because the rest of the product is a positive value (absolute values of the forces F1 and F2).

So the right answer is e) 180 degrees