Components: A helicopter is flying horizontally with a speed of 444 m/s over a hill that slopes upward with a 2% grade (that is, the "rise" is 2% of the "run"). What is the component of the helicopter's velocity perpendicular to the sloping surface of the hill?
A) 8.9 m/s
B) 220 m/s
C) 435 m/s
D) 444 m/s

Question

Quizplus · Accepted Answer

The perpendicular component of velocity can be found using trigonometry. The angle between the helicopter's velocity vector and the slope of the hill is given by the arctangent of the slope (2%), which is approximately 1.14 degrees. The perpendicular component is then given by the velocity multiplied by the cosine of this angle, which is approximately 444*cos(1.14) = 443.97 m/s. Rounded to one significant figure, this is 8.9 m/s.

Components: a Helicopter Is Flying Horizontally with a Speed of 444