Greatest elongation and escape velocity HELP

AI Thread Summary
The discussion revolves around two main physics problems: the elongation of wires and escape velocity. For the wires, it is clarified that since all wires are made of the same material, they possess the same Young's modulus, meaning the elongation will depend on their dimensions rather than the modulus itself. The participants emphasize the need to apply the correct equations relating elongation to the wire's length and diameter. Regarding escape velocity, it is noted that the escape velocity remains constant regardless of the launch angle, assuming no air resistance. Overall, the conversation highlights the importance of understanding material properties and the principles of motion in physics.
itheo92
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Homework Statement



Three wires are made of same materials. Which wire will have the greatest elongation?
wire1: length: 50cm, diameter: 0.5mm
wire2: length: 100cm, diameter: 1mm
wire3: length: 300cm, diameter: 3mm

Homework Equations


The Attempt at a Solution



I know, the wire having greatest elongation will have the greatest Young's modulus.
So, i have to calculate the young modulus from the given data of the three wires. but I can't get a equation to put.
actually I'm weak at the elasticity related issues, but I guess It's not too hard...

Homework Statement



The escape velocity from Earth is v. if the body is projected from the Earth in a direction of 45 degree to the vertical then it's escape velocity is??

Homework Equations


The Attempt at a Solution



I think, the escape velocity will not change...it's same for all direction...am I wrong?
 
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I would like to welcome you to these forums and would ask that you post separate unrelated questions in separate posts, and to please show an attempt at your work when posting, listing relevant equations.
itheo92 said:

Homework Statement



Three wires are made of same materials. Which wire will have the greatest elongation?
wire1: length: 50cm, diameter: 0.5mm
wire2: length: 100cm, diameter: 1mm
wire3: length: 300cm, diameter: 3mm

Homework Equations





The Attempt at a Solution



I know, the wire having greatest elongation will have the greatest Young's modulus.
this is not true
So, i have to calculate the young modulus from the given data of the three wires. but I can't get a equation to put.
It is given that all wires have the same material, therefore, they all have the same Young modulus, which is a property of the material structure.
actually I'm weak at the elasticity related issues, but I guess It's not too hard...
You'll need to list the relevant equation that relates elongation to Young's modulus and the given variables.

Homework Statement



The escape velocity from Earth is v. if the body is projected from the Earth in a direction of 45 degree to the vertical then it's escape velocity is??


Homework Equations





The Attempt at a Solution



I think, the escape velocity will not change...it's same for all direction...am I wrong?
You may very well be right, with the usual assumptions of no air resistance, etc., but why do you say that?
 

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