This following applet is [b]Impact force[/b]
Created by prof Hwang Modified by Ahmed
Original project [url=http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=1126.0]Impact force[/url]

Two objects with m1 and m2 respectively, released from the same height [b]h[/b] to the ground.
Under the condition: mass m2=2*m1

The time for object to reach the ground are T1 and T2 respectively,
Normally, the air reststance can be ignored for heavy objects, and we know that
T2=T1=\sqrt{2h/g}, where g is the gravity.

If the impact forces are F1 and F2 respectively.
What is the relation between F1 and F2?
A. F2>2*F1
B. F2=2*F1
C. F2<2*F1

The impact force F=?P/?T, where ?P is the momentum change during the impact and ?T is the impact time.
Both object drop from the same height, so the velocity when impact start is v=\sqrt{2gh},
So ?P2=2*?P1.
We need to know the relation between ?T2, ?T1 in order to compare F2/F1.
If ?T2= ?T1, then F2=2*F1.
However, is it true that ?T2= ?T1  ???
If ?T2> ?T1 , how to find out relation between F1 and F2?
You can check out the answer with the following simulation:

The impact time ?T and Faverege will be shown. F(t) is available, too!

The impact force is modeled withF(y)=-k*(y-y_0)-b*v_y.

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