Calculating Final Velocity with Given Work and Mass

AI Thread Summary
To find the final velocity of a 1.8 kg mass accelerated by 28.8 J of work, the relationship between work and kinetic energy is crucial. The formula "work done = change in kinetic energy" can be applied, where the initial kinetic energy is zero since the object starts from rest. By rearranging the equation to solve for final velocity, the formula becomes V = √(2A/m). This allows the calculation of the final velocity using the given work and mass values. Understanding the connection between work and kinetic energy is essential for solving this problem.
dasher141
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Homework Statement


I don't know how to solve this question.

28.8J of work were done in accelerating a mall of 1.8 kg from rest. Find its final velocity. I'm not sure which formula to use..

Homework Equations


F=ma
W=Fs
KE=1/2 mv^2

The Attempt at a Solution


I can't figure out which formula to use. (did some working in my workbook)
 
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Hi dasher141. http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif

Work and Energy have the same units, so are basically the same thing. I like the formula "work done = change in kinetic energy"
 
Last edited by a moderator:
A=Wk2-Wk1, Wk1=0 →
→ A=Wk1=mV2/2 → V=\sqrt{}(2A/m)
 
Sorry, made a mistake in second line. A=Wk2
 

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