Question

Vector vector a has a magnitude of 28 units and points in the positive y-direction. When vector vector b is added to vector a , the resultant vector vector a + vector b points in the negative y-direction with a magnitude of 12 units. Find the magnitude of vector b ?

Answer 1

28 + vector b   = -12

vector b  = -40  

vector b has magnitude 40 units in the negative y direction.