Earphone definition, a sound receiver that fits in or over the ear, as of a radio or telephone. See more.
Answer Wiki. If a rocket went straight up, it would either continue in that direction and leave Earth, or it would fall back down, depending on its velocity. Most rockets intend to enter orbit, which is an elliptical trajectory, and it's much more efficient to arc into this trajectory than to go straight up and then accelerate laterally.
A rocket essentially is a container propelled in one direction by exhaust going in the opposite direction. Rockets help spacecraft get into space, stay in space, and maneuver in space. The launch and flight of a rocket are governed by Newton's Laws of Motion.