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DLxX
Oct16-04, 09:53 PM
I need help with the following problem:

The block shown in fig 4-48 lies on a smooth plane tilted at an angle 22 degrees to the horizontal. (a)Determine the acceleration of the block as it slides down the plane. (b) If the block starts from rest 9.10m up the plane from its base, what will be the block's speed when it reaches the bottom of the incline? I'll attach a paint picture of the diagram I have. I really need help with part a, so if you are strapped for time I would really appreciate it if you could help me with a, I'm pretty sure I could figure out b. Btw it also says Ignore friction and that the coefficient of friction is .20 between the block and the incline plane. In the picture that I have attached I've also drawn what I think the free body diagram for this problem is, please correct it if it is wrong. It says nothing about the mass of the block so Im pretty sure some substituting formulas is going to be done and thats where Im having problems.

zeta101
Oct16-04, 10:21 PM
on your digram use the bit on the left to work out (using trig) what the component of force acts parallel to the incline. So you know the force, find the acceleration :)

Always work in algebra right until the end, the mass will cancel.

aekanshchumber
Oct16-04, 11:37 PM
Acceleration down the plane is "gsin22"
to calculate speed at the bottom,
V^2 = U^2 + 2a*s U initial velocity s distance covered