Hi I have a problem and a doubt regarding newton's laws of motion.(adsbygoogle = window.adsbygoogle || []).push({});

Consider three blocks of 5,2,5kg respectively placed one over the other and dropped from the top of a tower. (the 5 kg if at the top, 2kg in the middle and the 5kg at the bottom).

i) Find the acceleration of each block.

My calculations give me 'g'. Wont the acceleration be same for all three blocks?

ii) Find the contact forces between each block.

I got 0 as the answer for all the contact forces. I am not sure whether it is right though.

2) The second part of the question is: Consider the same details. Now, A 10N force is applied (directed upwards) on the 5kg block(which is at the bottom) from downwards.

i) Find 'a' between the blocks.

Here is my work:

5g - f2 = 5a

2g + f2 - f1 = 2a

5g + f1 - 10 = 5a

solving i got a = 55/6

ii) find the contact forces between the block.

f2 = 25/6 ; f1=575/6

Can someone please verify what I have done?Thanks!

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# Homework Help: Newton's law

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