Block launched from a spring across a surface with friction then up a slope

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Discussion Overview

The discussion revolves around a physics problem involving a block launched from a spring across a frictional surface and then up a slope. Participants explore the dynamics of the block's motion, including the effects of friction and acceleration, as well as the calculations necessary to determine where the block comes to rest.

Discussion Character

  • Homework-related
  • Mathematical reasoning
  • Technical explanation

Main Points Raised

  • One participant describes the initial conditions of the problem, including the mass of the block, spring constant, and the coefficients of friction.
  • Another participant mentions a similar problem from a textbook, indicating a slight variation in mass, which may affect the calculations.
  • A participant calculates the force exerted on the block using the spring constant and the compression distance, leading to an acceleration value.
  • The same participant details the motion of the block on both the frictionless and frictional surfaces, including calculations for time and velocity at various points.
  • A later reply corrects a previously stated velocity at the end of the frictional surface, indicating ongoing refinement of the calculations.

Areas of Agreement / Disagreement

Participants present various calculations and approaches, but there is no consensus on the final resting position of the block or the correctness of the calculations, indicating that multiple competing views remain.

Contextual Notes

Some calculations depend on assumptions about the coefficients of friction and the initial conditions. There are unresolved mathematical steps related to the block's motion on the frictional surface and the subsequent rise.

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A 170 g block is launched by compressing a spring of constant k=200N/m a distance of 15 cm. The spring is mounted horizontally, and the surface directly under it is frictionless. But beyond the equilibrium position of the spring end, the surface has coefficient of friction mu = 0.27. This frictional surface extends 85 cm, followed by a frictionless curved rise, as shown in the figure.
After launch, where does the block finally come to rest? Measure from the left end of the frictional zone.


Homework Equations


delta,x=(u^2)/2*mu*g

u0=1/2*k*x0^2


The Attempt at a Solution


I found u0 by using u0=1/2*k*x0^2 to be 2.25 and worked out delta,x to be 4.9967m which has me stumped as to what to do next? any help will be useful thanks
 
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Also i would like to add tht there is a similar problem in wolfson essential university physics volume 1 chapter 7 problem 57 pg 116 tht has a mass of 190 g instead of 170 g
 
Force exerted on the block= k*x=200*.15=30N
This force causes the block to move with an acceleration of 30/.17=176.47m/s2
Now the block moves on a non-frictional surface upto 15 cm and then on a frictional surface of 85 cm. Its motion on the latter surface is characterized by a deceleration of mu*g= 2.6m/s2.
1st surface: .15=.5*176.47*t*t implies t=0.04123
so velocity before it reaches second surface= .04123*176.47=7.276m/s
2nd surface: .85= 7.276*t - .5*2.6*t*t solve quadratic
t=.1196s
velocity at the end of 2nd surface= 7.276*.1196-2.6*.1196=.56m/s

the remaining you may figure it out yourself
 
Thanks for your help :)
 
though a correction

velocity at the end of 2nd surface= 7.276-2.6*.1196=6.97m/s
 

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