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1. https://c181ae78b6fc6200ce96232927a6...%20Physics.pdf
Question 9.
Apparantly the answer is C. How?
2. can anybody help meeeeeee?
3. (Original post by Unicorn16)
can anybody help meeeeeee?
The Young modulus (E), as you probably know, is stress over strain. If steel's E is twice that of brass, it means for the same stress, you get half the extension (because it is twice as stiff). If the combined wire is stretched, the stress is equal everywhere. That means the extension of the steel is half that of the brass, and therefore the ratio is 1/2 = 0.5. Does that make sense?
4. (Original post by Chlorophile)
The Young modulus (E), as you probably know, is stress over strain. If steel's E is twice that of brass, it means for the same stress, you get half the extension (because it is twice as stiff). If the combined wire is stretched, the stress is equal everywhere. That means the extension of the steel is half that of the brass, and therefore the ratio is 1/2 = 0.5. Does that make sense?
Ohh I get it.. yeah that makes sense!
Thanks so much
5. (Original post by Chlorophile)
The Young modulus (E), as you probably know, is stress over strain. If steel's E is twice that of brass, it means for the same stress, you get half the extension (because it is twice as stiff). If the combined wire is stretched, the stress is equal everywhere. That means the extension of the steel is half that of the brass, and therefore the ratio is 1/2 = 0.5. Does that make sense?
I used an algebraic method, not sure If it's done correctly but I did get the same answer???
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6. (Original post by MSB47)
I used an algebraic method, not sure If it's done correctly but I did get the same answer???
Looks right to me! You definitely don't need to do all of that for this question since you could work it out using intuition but yes, that does look correct.
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