Young's Modulus of Wire with 0.94 kN Load

AI Thread Summary
The discussion focuses on calculating the Young's modulus of a wire subjected to a 0.94 kN load. The wire, measuring 4.95 m in length and with a cross-sectional area of 0.103 cm², stretches by 6.55 mm under the load. Initial calculations yielded a Young's modulus of approximately 71.78 Pa, which was identified as incorrect. The correct formula application led to a revised Young's modulus of approximately 6.90 × 10^10 Pa. The final calculation was confirmed as accurate by participants in the discussion.
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A wire of length 4.95 m with a cross-sectional area of 0.103 cm^2 stretches by 6.55 mm when a load of 0.94 kN is hung from it. What is the Young's modulus for this wire?

FA = Y (delta L/L)

0.103 (cm^2) = 1.03 × 10-5 m^2
6.55 millimeters = 0.00655 meters

= 9221.4 N x 1.03 × 10-5 m^2 = .09498

0.00655m / 4.95m = 0.00132323232
.09498 / 0.00132323232 = 71.7787788 Pa ?

what did i do wrong?
 
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\Delta l = \frac{Fl}{YA} \Rightarrow Y = \frac{Fl}{\Delta l A}.
 
Y = 940N * 4.95m
------------
.00655m * 1.03(10^-5)m^2

Y = 6.90356083 × 10^10

Does this seem correct? thanks for the help
 
Yes, it seems correct.
 
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