What is the final velocity of a block on a ramp with given parameters?

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A block starts from rest at a height of 8m on a fixed inclined plane with a coefficient of friction of 0.19 and an incline angle of 29 degrees. The acceleration due to gravity is 9.8 m/s², and the block's mass is 4.5kg. The discussion centers on calculating the final velocity of the block at the bottom of the ramp, with the initial attempt yielding an incorrect acceleration and final velocity due to not accounting for the actual length of the incline. The correct approach involves using kinematics equations, specifically focusing on the relationship between acceleration, distance, and final velocity. The realization that the incline's length must be determined correctly is crucial for solving the problem accurately.
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Homework Statement


A block starts from rest at a heigh of 8m on a fixed inclined plane. The acceleration of gravity is 9.8m/s^2. What is the speed of the block at the bottom of the ramp? Answer in units of m/s.

Block mass = 4.5kg
coefficient of friction = 0.19
Angle of incline = 29 degrees
Distance from block to end of ramp = 8m


Homework Equations





The Attempt at a Solution



using a = (sin(theta)-ucos(theta)g I got 3.122 for a. However I'm not sure how to get a final velocity for the block from just the acceleration and distance.
 
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There's a kinematics equation that will directly give you the final velocity v2.

You know v1, a and d... you need v2... which equation will let you get it?
 
that would be sqrt of 2ax since vi is 0, but that answer comes out to 7.068 which is wrong so i must have my acceleration wrong
 
galuda said:
that would be sqrt of 2ax since vi is 0, but that answer comes out to 7.068 which is wrong so i must have my acceleration wrong

your acceleration looks right to me.

Did you use the right distance?

They give the height as 8m. But what is the length of the incline?
 
oh man I'm such an idiot. That would be the problem.
 
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