Young's Modulus of Wire with 0.94 kN Load

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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.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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