Let a wire be suspended from the ceiling (rigid support) and stretched by a weight $$W$$ attached at its free end. The longitudinal stress at any point of cross-sectional area $$A$$ of the wire is:
1. zero
2. $$\frac{2W}{A}$$
3. $$\frac{W}{A}$$
4. $$\frac{W}{2A}$$
Subtopic: Â Stress - Strain |
Â 66%
From NCERT
NEET - 2023
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The amount of elastic potential energy per unit volume (in SI unit) of a steel wire of length $$100$$ cm to stretch it by $$1$$ mm is: (Given: Young's modulus of the wire = $$2.0\times 10^{11}$$ Nm-2)
 1 $$10^{11}$$ 2 $$10^{17}$$ 3 $$10^{7}$$ 4 $$10^{5}$$
Subtopic: Â Potential energy of wire |
Â 62%
From NCERT
NEET - 2023
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Given below are two statements:
 Assertion (A): The stretching of a spring is determined by the shear modulus of the material of the spring. Reason (R): A coil spring of copper has more tensile strength than a steel spring of the same dimensions.

 1 Both (A) and (R) are true and (R) is the correct explanation of (A). 2 Both (A) and (R) are true but (R) is not the correct explanation of (A). 3 (A) is false but (R) is true. 4 (A) is true but (R) is false.
Subtopic: Â Shear and bulk modulus |
From NCERT
NEET - 2022
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NEET 2023 - Target Batch - Aryan Raj Singh
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NEET 2023 - Target Batch - Aryan Raj Singh

A wire of length $$L$$, area of cross section $$A$$ is hanging from a fixed support. The length of the wire changes to $$\mathrm{L}_1$$when mass $$M$$ is suspended from its free end. The expression for Young's modulus is:

 1 $$\frac{{Mg(L}_1-{L)}}{{AL}}$$ 2 $$\frac{{MgL}}{{AL}_1}$$ 3 $$\frac{{MgL}}{{A(L}_1-{L})}$$ 4 $$\frac{{MgL}_1}{{AL}}$$

Subtopic: Â Young's modulus |
Â 78%
From NCERT
NEET - 2020
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NEET 2023 - Target Batch - Aryan Raj Singh
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NEET 2023 - Target Batch - Aryan Raj Singh

When a block of mass $$M$$ is suspended by a long wire of length $$L$$, the length of the wire becomes ($$L+l$$). The elastic potential energy stored in the extended wire is:
1. $$\frac{1}{2}MgL$$
2. $$Mgl$$
3. $$MgL$$
4. $$\frac{1}{2}Mgl$$

Subtopic: Â Potential energy of wire |
Â 69%
From NCERT
NEET - 2019
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NEET 2023 - Target Batch - Aryan Raj Singh
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NEET 2023 - Target Batch - Aryan Raj Singh

The stress-strain curves are drawn for two different materials $$X$$ and $$Y.$$ It is observed that the ultimate strength point and the fracture point are close to each other for material $$X$$ but are far apart for material $$Y.$$ We can say that the materials $$X$$ and $$Y$$ are likely to be (respectively):

 1 ductile and brittle 2 brittle and ductile 3 brittle and plastic 4 plastic and ductile
Subtopic: Â Stress - Strain Curve |
Â 81%
From NCERT
NEET - 2019
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
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