Answer this one???

Question

I have two same caliber projectiles, both weighing the same. If one is fired out of a gun at 2000 fps and the other one is dropped free at the exact same time and height as the gun, would they both hit the ground at the same time? A different variation of the question would state: If two projectiles, both same in diameter and configuration but of different weights, were fired at the same time and at the same velocity, would they both hit the ground at the same time?

Answer 1

In answer to your questions: It depends!

If you assume no air resistance (or if the experiment is done in a vacuum), then the answer will not depend upon the weight of the objects in question (or any other attribute of them, such as shape).

In vacuum, if the projectile fired out of the gun is fired along a line parallel to the ground, then both projectiles will hit the ground at the same time, regardless of the velocity of the fired projectile.

Actually, there is another level of complexity that could be taken into account: both will hit the ground at the same time only if the Earth's curvature can be ignored! If the fired projective is moving fast enough (or from a high enough height) to proceed far enough toward (or past) the horizon before it hits the ground, then the fired projectile will hit the ground later than the dropped projectile. (At a truly very fast speed of firing, the projectile may never land, simply falling along a curve that never reaches the surface of the curving Earth. Then the projectile would be in orbit. That's what the Space Shuttle is doing.)

If the experiment is done in air, then the shape and weight of the projectiles would matter to some extent. For instance, a projectile of large density would fall to Earth quicker than one of the same weight but lower density (larger volume). To take an extreme example, a feather weighing the same as a penny would obviously fall slowly to Earth compared to the penny..

Answer 2

Assuming that your gun was firing parallel to the ground, then yes, both projectiles would hit the ground at the same time. The reason is that gravity is pulling down on both with the same amount of force, and while the moving projectile is moving at a greater speed, it's direction of speed is horizontal, not vertical. Hence, from a vertical standpoint, the initial speed of both projectiles is zero.

Answer 3

yes

provided that the one fired out of the gun had a up-down velocity of zero. ie. it was fired perfectly horizontally.

The idea here is the movemet in the verticle direction is due to acceleration due to gravity and follows the equation

d = Vot + 1/2 a t^2

where d = distance to ground
Vo is initial velocity ( = 0 if the gun was horizontal)
a = acceleration due to gravity (which is mass independant by the way)
t = time

if d = same for both cases and Vo = 0, then t is same...

Answer 4

If they're fired horizontally, then in both cases their intitial VERTICAL velocity is 0. So they'll both fall at the same rate and hit the ground simultaneously.

Answer 5

Yes surely. Here the mass of the body dosent play any role. So that dosent make any difference...........

Answer 6

Yes.

Answer 7

probably yes. try to reason it out with the help of newton's laws f motion

Answer 8

yes since downward acceleration is the same{g}