In the Challenger Deep of the Marianas Trench, the depth of seawater is 10.9 km and the pressure is 1.16×108 Pa (about 1.15×103 atm). If a cubic meter of water is taken from the surface to this depth, what is the change in its volume? (Normal atmospheric pressure is about 1.0×105 Pa. Assume that k for seawater is the same as the freshwater value given in Table 11.2.)
Ch 11: Equilibrium & Elasticity
Young & Freedman Calc15th EditionUniversity PhysicsISBN: 9780135159552Not the one you use?Change textbook
Chapter 11, Problem 42
A brass wire is to withstand a tensile force of 350 N without breaking. What minimum diameter must the wire have?
Verified step by step guidance1
First, identify the material properties of brass, specifically its tensile strength. Tensile strength is the maximum stress that a material can withstand while being stretched or pulled before breaking.
Next, use the formula for stress, which is defined as force divided by the area over which the force is applied: \( \text{Stress} = \frac{F}{A} \). Here, \( F \) is the force applied, and \( A \) is the cross-sectional area of the wire.
Since the wire is cylindrical, the cross-sectional area \( A \) can be expressed in terms of its diameter \( d \) using the formula for the area of a circle: \( A = \frac{\pi d^2}{4} \).
Rearrange the stress formula to solve for the diameter \( d \): \( d = \sqrt{\frac{4F}{\pi \times \text{Tensile Strength}}} \).
Substitute the given force (350 N) and the tensile strength of brass into the equation to find the minimum diameter required for the wire to withstand the force without breaking.

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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Tensile Strength
Tensile strength is the maximum amount of tensile stress that a material can withstand before failure. It is a critical property for materials subjected to stretching forces, such as wires. Understanding tensile strength helps determine the material's ability to resist breaking under tension.
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Stress and Strain
Stress is the force applied per unit area within materials, while strain is the deformation or displacement it causes. In this context, stress is calculated by dividing the tensile force by the cross-sectional area of the wire. The relationship between stress and strain is crucial for determining the wire's ability to handle the applied force.
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Cross-Sectional Area
The cross-sectional area of a wire is the area of its cut surface perpendicular to its length. For a circular wire, it is calculated using the formula A = π(d/2)^2, where d is the diameter. This area is essential for calculating stress, as a larger area can distribute the force more effectively, reducing stress and preventing breakage.
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Related Practice
Textbook Question
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Textbook Question
A square steel plate is 10.0 cm on a side and 0.500 cm thick. (a) Find the shear strain that results if a force of magnitude 9.0×105 N is applied to each of the four sides, parallel to the side. (b) Find the displacement x (in centimeters).
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Textbook Question
A specimen of oil having an initial volume of 600 cm3 is subjected to a pressure increase of 3.6×106 Pa, and the volume is found to decrease by 0.45 cm3. What is the bulk modulus of the material and the compressibility?
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