Two Similar objects with different weight falling at the same speed . (Revised again)?
Hello friends, There is no argument that the two objects fall at the same speed and acceleration as been proven by experiments.
The problem here is we know that the earths pull to the massive object is stronger as evidenced by its own weight.
But why it doesen't accelerate faster?
The equations has nothing to do with this because the scientist will formulate it differently if the heavier object fall faster.
indwilliam2006-05-29T02:43:14Z
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It's true - gravity pulls harder (i.e. more force) on a more massive (i.e. heavier) object. BUT that object is harder to accelerate - it has more interia. The two effects cancel each other out.
Clearly you don't like equations, but putting it in numbers can help:
If a 1kg object is pulled towards the earth, what will be the force, and what will be the acceleration? Force = mass * earth's gravitational field strength so Force = 1kg * 9.81N/kg Force = 9.81N (or 10N, roughly)
Acceleration = Force / Mass So Acc'n = 9.81N / 1kg = 9.81 m/s^2
Now consider the same for a 10kg object:
Force is now 98.1N (or 100N, roughly) So Acc'n = 98.1N / 10kg = 9.81 m/s^2
Two objects don't necessarily have the same acceleration, even in a vacuum. To see this, take two objects of different sizes and drop them on the moon.
Let's have the first object be a 1kg ball. Since the moon has a gravitational pull of about 1/6 the Earth's pull, this 1kg ball will accelerate at about g/6.
Now lets take a much bigger ball for the second object. Say, the Earth. If objects fell at the same rate of acceleration, the Earth would accelerate toward the moon at g/6 when dropped. But think about the moon moving toward the Earth instead of the Earth moving toward the moon. Then the moon would be falling toward the Earth at a rate of g, but obviously g does not equal g/6, so there must be something wrong. The problem is the assumption that objects fall with the same rate of acceleration.
The only reason for this phenomenon is the density of those objects. The one with greater density is usualy smaller than the one with smaller density. Subsequently, the air resistance affects the object with smaller density more intensively than the other one. In Vacuum, both objects fall at the same speed. This was proven by Galilei, who threw two similar objects of different weight from the Piza tower. The assistant on the ground saw both objects fell to the ground at the very same time. The confusion is usual when an iron ball and a feather are observed. But in Vacuum, they both fall down at the same speed. Recent attempts to revise Galilei's conclusions have led to the same results, although more precise measurements were applied (radar speedometer and contact detection cell).
If you took two object a metal marble and a feather.
Now flatten the marble very thin (feather like) then cut it up so the individual pieces are similar to the feather.
Now gravity will have the same effect on each piece of the marble as on the feather - no air resistance so everything falls at same rate / acceleration etc.
If all the pieces of marble fell very close together one above the other - no change - If the pieces were closer together they would eventually become on solid block again - but still no change as the whole could be treated as many pieces.
So no change even taking into effect gravitational attraction of the object as well as the planet.
without air resistance I know a feather and a coin will fall down to the moon's surface at the same time. The escape velocity of Earth's gravity is 9.8 meters per sec. So objects fall down at an equal acceleration of 9.8 meters per sec. Only thing that will challenge this is unlike the moon the Earth has an atmosphere which resists objects moving through it so a feather would flutter down slowly through the air while a heavier and more dense coin would push through the air more easily and hit the ground sooner. indwilliam has done the math.