Dear Ram Sai Charan,
Ans:- Let the initial velocity is U the final velocity is V Then from the given relation we have V²=0.75U²
Let the retardation for each block is =f
then V²=U² - 2f(9x)
where x=thickness of each plate
Let the total no of block required to stop it from it's initial velocity is n
Hence the excess no of plates required=36-9=27(ans)
Please feel free to post as many doubts on our discussion forum as you can. If you find any question
Difficult to understand - post it here and we will get you the answer and detailed solution very quickly. We
are all IITians and here to help you in your IIT JEE preparation.
All the best Ram Sai Charan !!!
Soumyajit Das IIT Kharagpur