Solving Motion of Block A on Wedge B

AI Thread Summary
The discussion revolves around solving the motion of block A on wedge B, both of mass m, with smooth surfaces. The user has derived equations related to the forces acting on the blocks but is struggling with the relationship between their accelerations and velocities. Key points include the need to apply the constraint that the blocks remain in contact, which affects their relative accelerations. A correction is noted regarding a dimensional error in the first equation presented. The conversation emphasizes the importance of understanding the dynamics of the system to find the displacement of block A after one second.
hav0c
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Homework Statement



A block A of mass m is placed over a wedge B of same mass m. Assuming all surface to be smooth. The displacement of block A is 1 sec if the system is released from rest is :

Homework Equations





The Attempt at a Solution


i have made fbds and have the relations-
1. ma1=(g-N1)/m
2.N1cos θ+mg cosθ=N2
3.ma2=sinθ(mg+N1)
now I am stuck
 

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There is one more equation. The blocks stay in contact so their velocities perpendicular to the contact are same. What can you say about the relative acceleration perpendicular to the contact?
 
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consciousness said:
There is one more equation. The blocks stay in contact so their velocities perpendicular to the contact are same. What can you say about the relative acceleration perpendicular to the contact?

What velocities are the same?
I don't get it
EDIT:Thanks i got it A1=a2sintheta
 
Last edited:
hav0c said:

Homework Statement



A block A of mass m is placed over a wedge B of same mass m. Assuming all surface to be smooth. The displacement of block A is 1 sec if the system is released from rest is :

Homework Equations





The Attempt at a Solution


i have made fbds and have the relations-
1. ma1=(g-N1)/m
2.N1cos θ+mg cosθ=N2
3.ma2=sinθ(mg+N1)
now I am stuck

Your first equation has a dimensional error.

I don't think the second equation would do any good. Your third equation is fine. Apply the constraint that blocks A and B stay together during the motion.
 
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