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.
In space, the rocket and the fire push off each other. Yes, if a rocket is on the ground, and fuel ignites under it, then some of the upward pressure on the rocket could come from the ignited fuel pushing off the ground.