A projectile is fired vertically from the surface of the Earth at 5 km/s. The projectile will
A) rise and fall back to the Earth's surface.
B) go into circular about the Earth.
C) go into an elliptical orbit about the Earth.
D) none of these

Question

Quizplus · Accepted Answer

The projectile will rise and then fall back to the Earth's surface because its speed (5 km/s) is less than the Earth's escape velocity (approximately 11.2 km/s). At 5 km/s, it does not have enough velocity to escape Earth's gravitational pull or to achieve orbit.

A Projectile Is Fired Vertically from the Surface of the Earth