The breaking stress in two wires of different materials $$A,B$$ are in the ratio:    $$\frac{S_A}{S_B}=\frac12,$$ while their radii are in the ratio:    $$\frac{r_A}{r_B}=\frac12.$$ The tensions under which they break are $$T_A$$ and $$T_B.$$ Then $$\frac{T_A}{T_B}=$$?
1. $$2$$
2. $$\frac14$$
3. $$\frac18$$
4. $$\frac1{2\sqrt2}$$
Subtopic:  Stress - Strain |
74%
From NCERT
Hints

A uniform rod of mass $$m,$$ having cross-section $$A$$ is pushed along its length $$(L)$$ by means of a force of magnitude, $$F.$$ There is no friction anywhere. Ignore the weight of the rod. The longitudinal stress in the rod, at a distance $$L \over 3$$ from the left end, is:

 1 tensile, $$F \over 3A$$ 2 compressive, $$F \over 3A$$ 3 tensile, $$2F \over 3A$$ 4 compressive, $$2F \over 3A$$
Subtopic:  Stress - Strain |
From NCERT
Hints

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:  Stress - Strain |
66%
From NCERT
NEET - 2023
Hints

A heavy mass is attached to a thin wire and is whirled in a vertical circle. The wire is most likely to break:

 1 when the mass is at the highest point 2 when the mass is at the lowest point 3 when the wire is horizontal 4 at an angle of $$\cos^{-1}(\frac{1}{3})$$ from the upward vertical

Subtopic:  Stress - Strain |
73%
From NCERT
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

The maximum load a wire can withstand without breaking when its length is reduced to half of its original length, will:

 1 be doubled 2 be halved 3 be four times 4 remain the same

Subtopic:  Stress - Strain |
60%
From NCERT
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

A mild steel wire of length $$\mathrm{2L}$$ and cross-sectional area $$A$$ is stretched, well within the elastic limit, horizontally between two pillars (figure). A mass $$m$$ is suspended from the mid-point of the wire. Strain in the wire is:

1. $$\frac{x^2}{2 L^2}$$
2. $$\frac{x}{\mathrm{~L}}$$
3. $$\frac{x^2}{L}$$
4. $$\frac{x^2}{2L}$$

Subtopic:  Stress - Strain |
From NCERT
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

Hooke's law is applicable for:

 1 elastic materials only 2 plastic materials only 3 elastomers only 4 all of these

Subtopic:  Hooke's Law |
68%
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
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:  Stress - Strain Curve |
81%
From NCERT
NEET - 2019
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

The figure shows the strain-stress curve for a given material. What is Young’s modulus for this material?

1. $$7.5\times10^{11}~\text{Nm}^{-2}$$
2. $$7.5\times10^{10}~\text{Nm}^{-2}$$
3. $$7.5\times10^{9}~\text{Nm}^{-2}$$
4. $$7.5\times10^{-10}~\text{Nm}^{-2}$$

Subtopic:  Stress - Strain Curve |
79%
From NCERT
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

The stress-strain graphs for materials $$A$$ and $$B$$ are shown in the figure. Strength of material $$A$$ is:
(The graphs are drawn to the same scale)

 1 greater than material $$B$$ 2 equal to material $$B$$ 3 less than material $$B$$ 4 insufficient data

Subtopic:  Stress - Strain Curve |
72%
From NCERT
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints