Projectile Motion - Distance between Packages

AI Thread Summary
When a package is dropped from a plane, the distance between two packages dropped at different times will increase due to gravitational acceleration. The first package falls 4.9 meters in the first second, while the second package, dropped one second later, starts from rest and falls 4.9 meters in its first second. As time progresses, the first package continues to fall further, increasing the vertical distance between the two. The horizontal velocity remains constant for both packages, but the vertical distance grows because of the acceleration due to gravity. Therefore, the correct answer is that the distance between the packages increases over time.
MohammadG
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Homework Statement


A package of supplies is dropped from a plane and one second later a second package is dropped. Neglecting air resistance, the distance between the falling packages will:

A) Be constant
B) decrease
C) increase
D) depend on their weight

Homework Equations


Sv=1/2 av t^2

The Attempt at a Solution


Well I thought it would be constant but my teacher informed me it was C. He didn't explain why though. I'm assuming the planes speed is constant, which means both package will be subject to the same horizontal component of velocity. However the first package would have already fallen (4.9 meters) downwards due to gravitational acceleration. The second one would then be released and would be subject to the same forces. (As horizontal component of velocity would remain constant)

So I don't see how they would have an increasing distance.

My idea was,

Sv=1/2(9.8)(1)^2 = 4.9

Sv=1/2(9.8)(2)^2 = 19.6

Sv=1/2(9.8)(3)^2 = 44.1


Therefore, when package 1 is at 4.9, package 2 is at 0 (displacement). [difference 4.9 m]
When package 1, is at 19.6, package 2 is at 4.9. [difference of 14.7m]

etc and its increasing.

I think this is the right answer. How can I explain this in a sentence using physics terms. Its a multiple choice question so no calculations were needed even though I did some.

Thanks.
 
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Which direction, x-or -y is the question referring?
 
physicsisgrea said:
Which direction, x-or -y is the question referring?

Both x and y. However as the horizontal component won't change, we can just use the vertical component correct?

As both have the same trajectory.
 
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