Block hitting a spring down an incline

AI Thread Summary
The discussion focuses on a physics problem involving a block on a frictionless incline and its interaction with a spring. The block, with a mass of 19 kg, is released from rest and compresses the spring by 3.6 cm before stopping. The correct distance the block moves down the incline has been calculated accurately, while the calculation for the block's speed as it touches the spring is incorrect. There is confusion regarding the formula used for speed, particularly whether the mass is properly included in the calculation. Clarification on the formula and its components is sought to resolve the issue.
AnkhUNC
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Homework Statement


In Fig, a block of mass m = 19 kg is released from rest on a frictionless incline of angle θ = 34°. Below the block is a spring that can be compressed 4.5 cm by a force of 210 N. The block momentarily stops when it compresses the spring by 3.6 cm. (a) How far does the block move down the incline from its rest position to this stopping point? (b) What is the speed of the block just as it touches the spring?

http://edugen.wiley.com/edugen/courses/crs1650/art/qb/qu/c08/fig08_41.gif


Homework Equations





The Attempt at a Solution



I found (a) = 0290429321 meters which is correct.
For (b) I tried the following v = sqrt(K*.036m^2)/19kg. But this is also incorrect. Any ideas?
 
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AnkhUNC said:
I found (a) = 0290429321 meters which is correct.
For (b) I tried the following v = sqrt(K*.036m^2)/19kg. But this is also incorrect. Any ideas?

No decimal point for (a)?

For (b), your approach is correct, but I'm unable to make out if the sqrt covers the 19 in the denominator.
 
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