What are some of the major challenges facing space travel today?

In a bumper car arena, two cars of equal mass are heading straight toward each other. the orange one is traveling at a speed of 5 meters per second. the green one is traveling at a speed of 2 meters per second. which of the forces most affects the motion of the bumper cars after they collide? a) gravity b) friction c) the other car d) wind resistance

The rocket is fired vertically and tracked by the radar station shown. when θ reaches 66°, other corresponding measurements give the values r = 32700 ft, r¨ = 85 ft/sec2, and θ˙ = 0.019 rad/sec. calculate the magnitudes of the velocity and acceleration of the rocket at this position.

Argon, neon, and xenon are examples of