Question

in a video game, a flying spaceship moves at a constant velocity of 20 m/s in the positive - x direction. the spaceship hits an obstacle and moves in the opposite direction with a constant velocity of 10 m/s. whats the change in velocity of the spaceship?

a. - 30 m/s
b. - 10 m/s
c. 10 m/s
d. 30 m/s

Explanation:

Step1: Define velocities

Let initial velocity \( v_i = +20 \, \text{m/s} \) (positive direction), final velocity \( v_f = -10 \, \text{m/s} \) (opposite direction).

Step2: Calculate change in velocity

\( \Delta v = v_f - v_i = (-10) - 20 = -30 \, \text{m/s} \)

Answer:

A. -30 m/s