If you were able to go to the top of a tall building and simultaneously drop an apple and a basketball,?

Question

If you were able to go to the top of a tall building and simultaneously drop an apple and a basketball, they would both hit the gound at about the same instant because
a. the force of gravity on them is equal.
b. they have the same mass.
c. air resistance on both is the same.
d. they have the same amount of kinetic energy.

Answer 1

The basketball and the apple would only hit the ground if their respective densities and coefficients of friction were the same. An apple has a specific gravity of almost 1, and a basketball is a lot less than 1, so they would not hit the ground at the same time. It would be a combination of a, b, c, and d - so there is no right answer.

The answer needs to account for the air density, the specific gravity or density of the objects, the coefficient of drag of the objects being dropped, and the acceleration due to gravity. If the basketball and the apple were dropped in a vacuum, then 'a' would apply, and they would both reach the ground at the same time, and so would a brick and a feather.

Kinetic energy of a falling object is a function of the force of gravity (in this case the same for both objects), the velocity of the objects, and the mass of the objects. Therefore the kinetic energy will vary according to their terminal velocity and mass according to F=MV.

Answer 2

They wouldn't hit the ground together! Galilleo proved that if you drop two objects of a tall building, as long as the air resistance on them is the same, two objects will fall at the same rate no matter what there mass, or force of gravity. The kinetic energy makes no difference in this case because they both have the same amount anyway. (they are both dropped no pushed)

However, clearly, the air resistance of a basket-ball and an apple are NOT the same, so the apple will experience less friction and will fall faster.

Its like if you have a big parachute and a sainsburies bag, and two people hold them above themselves and drop from a tall buliding... the one with the sainsburies bag has less resitance and falls faster... therefore splat.

So the whole question is wrong, they would NOT hit the fround at the same instant. Sorry!

Answer 3

a...and c, I think. I believe that in that scenario, c is the deciding factor. Because the force of gravity would be the same for a penny and a sheet of paper, as well. But due to the difference in air resistance, the penny would hit the ground first.

Added: The answers claiming that all of the above are responsible, are mistaken. I highly doubt the apple and the basketball have the same mass (or kinetic energy, since mass is a factor in determining that). And even so, for objects falling on Earth, the effect of an object's mass on the object's rate of acceleration is negligible. If air resistance is not taken into consideration, all things in freefall on Earth will accelerate downward at a rate of 9.8 m/s^2, no matter what their mass is.

Answer 4

Not (A) because the force of gravity on them is not equal.

Not (B) because they do not have the same mass.

Not (C) because the air resistance depends on size and shape, which are not the same.

Not (D) because they do not have the same kinetic energy.

The correct answer is not given; it is that acceleration due to gravity is the same for all objects, regardless of mass.

However, I would choose (C), because given that two objects falling from a very tall height did in fact hit the ground at the same time, (C) is an appropriate inference.

Answer 5

I would suppose, to hit the ground at equal timings.. they would naturally have to have the same gravity force, air resistance and kinetic energy. As well as being from the same mass..

That's what they taught us back in school, I think.

All conditions must be similar or rather equal.

Having same inputs will lead to a same output if the process is the same.

It's been long since i've last taken phsyics.. I could be mixing things together.

Answer 6

The basket ball would bounce and the apple would splat

Answer 7

a