What acceleration of blocks in given condition.

[vkash]

see this image
https://docs.google.com/leaf?id=0B5...AtMTZmMDU5ZGIwOGQx&hl=en_GB&authkey=CL3RqN4O"

something about question:=> a block M₁ placed over M₂ Nd M₂ placed on the earth.A constant force F is applied in upward direction. You have to tell about the motion of M₁ and M₂ in condition as given below pulleys are frictionless and only friction is in between M₁ and M₂.

first case In first case friction is zero between both blocks so will block M₁ and M₂ is zero.
second case friction between M₁ and M₂ is very large.

tell me about acceleration about the bodies in both cases if you think more variable required to answer then introduce them.
My mind says that there will acceleration in Block M₂ will something in second case but sometimes i think that acceleration of M₂ will zero in both cases. I say there will acceleration in block M₂ zero because force is in upward direction(this logic seeming wrong) but i think there will acceleration in block M₂ because a force will act due to tension(string between M₁ and pulley.

Guys put your thoughts here i will thankful for you.

 

[wbandersonjr]

First off, think about what forces will act on block M2. What force do you think would cause it to accelerate, what force is missing that you think would not cause acceleration? Why?

 

[vkash]

First off, think about what forces will act on block M2. What force do you think would cause it to accelerate, what force is missing that you think would not cause acceleration? Why?

need FBD see it
https://docs.google.com/leaf?id=0B5...QtOWNiNzA5YWUyYzE1&hl=en_GB&authkey=CPGLgL8N"
this is large image so download it before viewing else it will hard to see what's there.
thank's for replying. Waiting for other replies.

 

[Libohove90]

need FBD see it
https://docs.google.com/leaf?id=0B5...QtOWNiNzA5YWUyYzE1&hl=en_GB&authkey=CPGLgL8N"
this is large image so download it before viewing else it will hard to see what's there.
thank's for replying. Waiting for other replies.

In the first case, the acceleration of M2 is zero because there is no friction between M1 and M2. Thus, the acceleration of M1 will not affect M2.

In the second case, M2 will accelerate because there is friction between M1 and M2. If M1 accelerates, then the frictional force will cause M2 to accelerate forward. By how much? Depends on the amount of friction. The accelerations of the boxes can be found by applying Newton's Third Law since the frictional forces they exert on each other are equal. Since their masses are not equal, consequently, their accelerations will not equal.

 

[vkash]

In the first case, the acceleration of M2 is zero because there is no friction between M1 and M2. Thus, the acceleration of M1 will not affect M2.

In the second case, M2 will accelerate because there is friction between M1 and M2. If M1 accelerates, then the frictional force will cause M2 to accelerate forward. By how much? Depends on the amount of friction. The accelerations of the boxes can be found by applying Newton's Third Law since the frictional forces they exert on each other are equal. Since their masses are not equal, consequently, their accelerations will not equal.

why the T (tension) I round in diagram (i put here in last post) make a change ? this tension is in both cases.