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Name: Vincent
Status: student
Age: 12
Location: N/A
Country: N/A
Date: 1999 

why do different objects of different weight drop at the same speed in air.

Over short distances, indeed you are right. Sir Isaac Newton found that the acceleration of an object directly increased as the force on that object increased. He also found that the acceleration decreased as the mass increased. In equation form, it looks like:

a = F/m

If you double the mass, you also double the attractive force the object has toward the earth. The equation looks like:

a = 2F/2m

The 2's cancel, giving the same equation as before:

a = F/m

So you see, the rate at which the falling object increases its speed is independent of mass!

---Nathan A. Unterman

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