Question

vector addition quiz l - mu
for the winter, a duck flies 15.0 m/s due south against a gust of wind with a velocity of 2.5 m/s north. what is the resultant velocity of the duck?
○ 7.5 m/s south
○ 7.5 m/s north
○ 12.5 m/s south
○ 12.5 m/s north

Explanation:

Step1: Assign direction signs

Let south = positive, north = negative.
Duck's velocity: $v_d = 15.0\ \text{m/s}$
Wind's velocity: $v_w = -2.5\ \text{m/s}$

Step2: Calculate resultant velocity

Add the two velocities.
$$v_{resultant} = v_d + v_w = 15.0 + (-2.5) = 12.5\ \text{m/s}$$
Positive value means direction is south.

Answer:

12.5 m/s south