Question

A pedestrian walks at a rate of 6 km per hour East. The wind pushes him northwest at a rate of 13 km per hour. Find the magnitude of the resultant vector.

(Round to the nearest hundredth)

Answer 1

The pedestrian vector would be (6,0)

The wind vector would be (-13cos(45), 13sin(45)) = (-9.1924, 9.1924)

Now add the two vectors: (6, 0) + (-9.1924, 9.1924) = (-3.1924, 9.1924)

This is the resultant vector in rectangular coordinates. Now calculate the magnitude of the vector.

Magnitude is always positive and is : sqrt[x-coord2 + y-coord2]

Magnitude = sqrt(94.6915599) = 9.73 ( rounded to the nearest hundredth)