Solve the given problem:
 
An object of mass \(4\) \(kg\) is dropped from a height of \(8\) \(m\). It hits the ground and rebounds with the same speed. Find the change in momentum. (Take \(g\ =\ 10\)  )
 
Change in momentum \(=\)  \(kg\)ms1
 
Important!
Note: Enter your answer with two decimal digit