Relationship of Young's modulus and impulse force

AI Thread Summary
The discussion centers on the relationship between Young's modulus of a spring and impulse force, highlighting the necessity of knowing the cross-sectional area and spring constant for accurate calculations. Participants clarify that Young's modulus, often denoted as Y, is distinct from the elastic modulus used in other contexts, such as stretched wires. The equation Y=kL0 is emphasized, indicating that Young's modulus incorporates the spring's structural details, making it more relevant than the elastic modulus in this scenario. The impulse force equation J=∫F.dt is noted, with the limitation that it simplifies to J=Ft only if the force remains constant. Overall, understanding the distinctions between these terms is crucial for solving the problem effectively.
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Homework Statement



Is that possible to obtain the a relationship between Young's modulus of a spring and impulse force with below information ? I personally think that we cannot if without the given cross-sectional area A and the given spring constant k.

The particle is connect to a elastic spring, then an external impulse force horizontally was added to it.
(Smooth plate)

The given values are :

Particle mass ''m'', spring of modulus of elasticity ''E'', spring's natural length ''L'', received impulse ''J'', impulse reaction time ''t'', displacement ''x''

2. Homework Equations


a327da84721b22b1fbcf2d925192512a3fd31d03


The Attempt at a Solution


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F = kx => J/t = (EA/L) * (x)

Looks like the area is an essential value or we cannot express the equation for them.
 
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Howard_SSS said:
a327da84721b22b1fbcf2d925192512a3fd31d03
E there is not Young's modulus of a spring. Young's modulus, often written as Y, is related to the spring constant k by Y=kL0.
Howard_SSS said:
F = kx => J/t
Not in this case. J=∫F.dt. You can only simplify that to J=Ft if F is constant.
 
haruspex said:
E there is not Young's modulus of a spring. Young's modulus, often written as Y, is related to the spring constant k by Y=kL0.

Not in this case. J=∫F.dt. You can only simplify that to J=Ft if F is constant.
Thanks for this reminding.

For Y=k*L0, may I know why you can remove the A (cross sectional area) ?
 
Howard_SSS said:
Thanks for this reminding.

For Y=k*L0, may I know why you can remove the A (cross sectional area) ?
EA, where E is the elastic modulus (not Young's modulus) is for a stretched wire. A regular coiled spring works by torsion, not by stretching of the material. Young's modulus is more suitable, and already incorporates the details of the spring structure. It is defined as the force per fractional change in spring length, so Y=kL0.
 
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