Which one of the following statements is incorrect?

 1 Rolling friction is smaller than sliding friction. 2 Limiting value of static friction is directly proportional to the normal reaction. 3 Frictional force opposes the relative motion. 4 Coefficient of sliding friction has dimensions of length.
Subtopic:  Friction |
77%
From NCERT
NEET - 2018
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 block of mass $$m$$ is placed on a smooth inclined wedge $$ABC$$ of inclination $$\theta$$ as shown in the figure. The wedge is given an acceleration '$$a$$' towards the right. The relation between $$a$$ and $$\theta$$ for the block to remain stationary on the wedge is:

1. $$a = \frac{g}{\text{cosec}\theta}$$
2. $$a = \frac{g}{\text{sin}\theta}$$
3. $$a = g~\text{cos}\theta$$
4. $$a = g~\text{tan}\theta$$

Subtopic:  Application of Laws |
78%
From NCERT
NEET - 2018
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

One end of the string of length l is connected to a particle of mass m and the other end is connected to a small peg on a smooth horizontal table. If the particle moves in a circle with speed v, the net force on the particle (directed towards the centre) will be: (T represents the tension in the string)

 1 $$T$$ 2 $$T+\frac{m v^2}{l}$$ 3 $$\mathrm{T}-\frac{m v^2}{l}$$ 4 $$\text{Zero}$$
Subtopic:  Uniform Circular Motion |
52%
From NCERT
NEET - 2017
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 massless and inextensible string connects two blocks $$\mathrm{A}$$ and $$\mathrm{B}$$ of masses $$3m$$ and $$m,$$ respectively. The whole system is suspended by a massless spring, as shown in the figure. The magnitudes of acceleration of $$\mathrm{A}$$ and $$\mathrm{B}$$ immediately after the string is cut, are respectively:

 1 $$\frac{g}{3},g$$ 2 $$g,g$$ 3 $$\frac{g}{3},\frac{g}{3}$$ 4 $$g,\frac{g}{3}$$

Subtopic:  Spring Force |
69%
From NCERT
NEET - 2017
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 spring of force constant k is cut into lengths of ratio 1:2:3. They are connected in series and the new force constant is ${k}^{\text{'}}$. If they are connected in parallel and force constant is  is

(1) 1:6

(2) 1:9

(3) 1:11

(4) 6:11

Subtopic:  Spring Force |
76%
From NCERT
NEET - 2017
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 bullet of mass 10g moving horizontal with a velocity of 400 m/s strikes a wood block of mass 2 kg which is suspended by light inextensible string of length 5 m. As result, the centre of gravity of the block found to rise a vertical distance of 10 cm. The speed of the bullet after it emerges of horizontally from the block wiil be

(1) 100 m/s

(2) 80 m/s

(3) 120 m/s

(4) 160 m/s

Subtopic:  Newton's Laws |
55%
From NCERT
NEET - 2016
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 car is negotiating a curved road of radius R. The road is banked at angle $\mathrm{\theta }$. The coefficient of friction between the tyres of the car and the road is ${\mathrm{\mu }}_{\mathrm{s}}$. The maximum safe velocity on this road is

1. $\sqrt{\mathrm{gR}\left(\frac{{\mathrm{\mu }}_{\mathrm{s}}+\mathrm{tan\theta }}{1-{\mathrm{\mu }}_{\mathrm{s}}\mathrm{tan\theta }}\right)}$

2. $\sqrt{\frac{\mathrm{g}}{\mathrm{R}}\left(\frac{{\mathrm{\mu }}_{\mathrm{s}}+\mathrm{tan\theta }}{1-{\mathrm{\mu }}_{\mathrm{s}}\mathrm{tan\theta }}\right)}$

3. $\sqrt{\frac{\mathrm{g}}{{\mathrm{R}}^{2}}\left(\frac{{\mathrm{\mu }}_{\mathrm{s}}+\mathrm{tan\theta }}{1-{\mathrm{\mu }}_{\mathrm{s}}\mathrm{tan\theta }}\right)}$

4. $\sqrt{{\mathrm{gR}}^{2}\left(\frac{{\mathrm{\mu }}_{\mathrm{s}}+\mathrm{tan\theta }}{1-{\mathrm{\mu }}_{\mathrm{s}}\mathrm{tan\theta }}\right)}$

86%
From NCERT
NEET - 2016
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 rigid ball of mass $$M$$ strikes a rigid wall at $$60^{\circ}$$ and gets reflected without loss of speed, as shown in the figure. The value of the impulse imparted by the wall on the ball will be:

 1 $$Mv$$ 2 $$2Mv$$ 3 $$\frac{Mv}{2}$$ 4 $$\frac{Mv}{3}$$
Subtopic:  Newton's Laws |
75%
From NCERT
NEET - 2016
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 car is negotiating a curved road of radius $$R$$. The road is banked at an angle $$\theta$$. The coefficient of friction between the tyre of the car and the road is $$\mu_s$$. The maximum safe velocity on this road is:
1. $$\sqrt{\operatorname{gR}\left(\frac{\mu_{\mathrm{s}}+\tan \theta}{1-\mu_{\mathrm{s}} \tan \theta}\right)}$$
2. $$\sqrt{\frac{\mathrm{g}}{\mathrm{R}}\left(\frac{\mu_{\mathrm{s}}+\tan \theta}{1-\mu_{\mathrm{s}} \tan \theta}\right)}$$
3. $$\sqrt{\frac{\mathrm{g}}{\mathrm{R}^2}\left(\frac{\mu_{\mathrm{s}}+\tan \theta}{1-\mu_{\operatorname{s}} \tan \theta}\right)}$$
4. $$\sqrt{\mathrm{gR}^2\left(\frac{\mu_{\mathrm{s}}+\tan \theta}{1-\mu_{\mathrm{s}} \tan \theta}\right)}$$