gracy said:
if any object is in aircraft so it will have velocity same as that of aircraft ,right ? and say in case it is thrown out of aircraft in between will it retain that velocity provided that no external force act on it?
when you throw something out of the aircraft, it implies directly that external force IS acting on it.
if you drop something from aircraft, like a bomb, then you release the bomb, and allow gravity to take over the effect.
initially the bomb carries certain amount of forward velocity, but you have to realize that the aircraft is no longer attached to the bomb anymore. When the aircraft is no longer attached to bomb, aircraft speed cannot keep the bomb from moving forward similarly as the aircraft. Aircraft velocity force no longer affects bomb. The bomb does have momentum though.
The difference is that the direction of the forces changes to my understanding, when you compare dropped bomb from aircraft, into a bomb inside the aircraft when aircraft is moving forward.
It's a ballistic projectile with no forces effecting it except gravity and drag. Also, the bomb would produce certain amount of lift also, because of its bodyshape I would imagine, at least initially when the bomb is "sideways" instead of pointed downwards. This is how sometimes GPS guided bombs have guiding "flight surfaces" which can aim the bombs, and bombs are encased into aerodynamic shells, (JDAM). Also different so-called gliding bombs have been invented in which the purpose is the maximise the flight time of the bomb. (flight time forwards)When you drop the bomb, aircraft velocity forward, (force vector) no longer affects upon the bomb.
However, because the bomber was moving, and it dropped the bomb, it stands to reason that momentum was conserved in the bomb.
I'm not terribly sure how one should interpret the effect of forward flying bomb, from the result of bomb being dropped from forward flying aircraft. There does exist force for short time period somehow, when the bomb is dropped from aircraft.
But clearly, when the bomb is droppped, the aircraft velocity no longer has any meaning to the bomb's movements. You could slow down in the aircraft, after you drop the bomb, it would not affect the bomb's velocity anymore.
The dropped bomb pushes against air, air pushes against bomb, this creates drag.
Dropped bomb pulls toward Earth and Earth pulls toward dropped bomb, this creates gravity.
Dropped bomb should now tend to accelerate toward ground, because gravity would be the principal force.
Then the drag keeps increasing, because speed has increased massively at this point. The speed is downwards though at this point. (towards core of earth) Gravity is the force vector now, I suppose.
When speed increases, because gravity is more than drag in dropped bombs (aerodynamic shape of bombs), then this means acceleration has occured.
But because speed increases, it should be remembered that drag increases when speed increases. Eventually there comes point when drag and gravity are balanced. Then acceleratin stops and bomb keeps falling at the same speed to Earth's core.
Earth is also dropping slightly toward the bomb (but the effect of Earth's movement or acceleration toward the bomb is truly miniscule to be honest)
