← Back to Physics-I

NLM

968 Questions Start Allen Test
All Exams Allen Advance Errorless
JEE (Main) March 2021 Q101 Errorless Critical Thinking-friction MCQ
A solid cylinder of mass m is wrapped with an inextensible light string and, is placed on a rough inclined plane as shown in the figure. The frictional force acting between the cylinder and the inclined plane is [The coefficient of static friction, $\mu_{s}$ is 0.4]
A.
$\frac {7}{2} m g$
B.
5mg
C.
$\frac {m g}{5}$
D.
0
JEE (Main) July 2021 Q102 Errorless Critical Thinking-friction MCQ
The normal reaction 'N' for a vehicle of 800 kg mass, negotiating a turn on a $30^{\circ}$ banked road at maximum possible speed without skidding is ____ $\times 10^{3}$ kg m/s $^{2}$
A.
10.2
B.
7.2
C.
12.4
D.
6.96
JEE (Main) 2020 Q103 Allen JEE Main PYQ Numerical
A small block starts slipping down from a point B on an inclined plane AB, which is making an angle $\theta$ with the horizontal section BC is smooth and the remaining section CA is rough with a coefficient of friction $\mu$ . It is found that the block comes to rest as it reaches the bottom (point A) of the inclined plane. If BC = 2AC, the coefficient of friction is given by $\mu = k \tan\theta$ . The value of k is ____.
JEE (Main) 2020 Q104 Allen JEE Main PYQ MCQ
An insect is at the bottom of a hemispherical ditch of radius 1m. It crawls up the ditch but starts slipping after it is at height h from the bottom. If the coefficient of friction between the ground and the insect is 0.75, then h is: $(g = 10 \, ms^{-2})$
A.
0.80 m
B.
0.60 m
C.
0.45 m
D.
0.20 m
JEE (Main) 2020 Q105 Allen JEE Main PYQ MCQ
A mass of 10 kg is suspended by a rope of length 4 m, from the ceiling. A force F is applied horizontally at the mid-point of the rope such that the top half of the rope makes an angle of $45^{\circ}$ with the vertical. Then F equals: (Take $g = 10 \, ms^{-2}$ and the rope to be massless)
A.
100 N
B.
90 N
C.
75 N
D.
70 N
JEE (Main) Jan. 2020 Q106 Errorless Critical Thinking MCQ
A mass of 10 kg is suspended by a rope of length 4 m, from the ceiling. A force F is applied horizontally at the mid-point of the rope such that the top half of the rope makes an angle of $45^{\circ}$ with the vertical. Then F equals (Take $g = 10ms^{-2}$ and the rope to be massless)
A.
100 N
B.
90 N
C.
75 N
D.
70 N
JEE (Main) Jan. 2020 Q107 Errorless Critical Thinking MCQ
A uniformly thick wheel with moment of inertia I and radius R is free to rotate about its centre of mass (see fig). A massless string is wrapped over its rim and two blocks of masses $m_{1}$ and $m_{2}(m_{1}>m_{2})$ are attached to the ends of the string. The system is released from rest. The angular speed of the wheel when $m_{1}$ descents by a distance h is
A.
$\left[\frac{m_1 + m_2}{(m_1 + m_2)R^2 + I}\right]^{\frac{1}{2}}gh$
B.
$\left[\frac{2(m_1 - m_2)gh}{(m_1 + m_2)R^2 + I}\right]^{\frac{1}{2}}$
C.
$\left[\frac{2(m_1 + m_2)gh}{(m_1 + m_2)R^2 + I}\right]^{\frac{1}{2}}$
D.
$\left[\frac{(m_1 - m_2)}{(m_1 + m_2)R^2 + I}\right]^{\frac{1}{2}}gh$
JEE (Main) Sep. 2020 Q108 Errorless Critical Thinking-friction MCQ
An insect is at the bottom of a hemispherical ditch of radius 1 m. It crawls up the ditch but starts slipping after it is at height h from the bottom. If the coefficient of friction between the ground and the insect is 0.75, then h is $(g = 10ms^{-2})$
A.
0.80 m
B.
0.60 m
C.
0.45 m
D.
0.20 m
JEE (Advanced) 2020 Q109 Errorless Integer Type Questions-friction Numerical
Put a uniform meter scale horizontally on your extended index fingers with the left one at 0.00 cm and the right one at 90.00 cm. When you attempt to move both the fingers slowly towards the center, initially only the left finger slips with respect to the scale and the right finger does not. After some distance, the left finger stops and the right one starts slipping. Then the right finger stops at a distance $x_{R}$ from the center (50.00 cm) of the scale and the left one starts slipping again. This happens because of the difference in the frictional forces on the two fingers. If the coefficients of static and dynamic friction between the fingers and the scale are 0.40 and 0.32, respectively, the value of $x_{R}$ (in cm) is ____
JEE (Main) 2019 Q110 Allen JEE Main PYQ MCQ
Two blocks A and B of masses $m_{A} = 1 \, kg$ and $m_{B} = 3 \, kg$ are kept on the table as shown in figure. The coefficient of friction between A and B is 0.2 and between B and the surface of the table is also 0.2. The maximum force F that can be applied on B horizontally, so that the block A does not slide over the block B is: (Take $g = 10 \, m/s^{2}$ )
A.
$16N$
B.
$40N$
C.
$12N$
D.
$8N$
JEE (Main) 2019 Q111 Allen JEE Main PYQ MCQ
A ball is thrown upward with an initial velocity $V_{0}$ from the surface of the earth. The motion of the ball is affected by a drag force equal to $m\gamma v^{2}$ (where m is mass of the ball, $\upsilon$ is its instantaneous velocity and $\gamma$ is a constant). Time taken by the ball to rise to its zenith is
A.
$\frac{1}{\sqrt{\gamma g}}\sin^{-1}\left(\sqrt{\frac{\gamma}{g}}V_{0}\right)$
B.
$\frac{1}{\sqrt{\gamma g}}\tan^{-1}\left(\sqrt{\frac{\gamma}{g}}V_{0}\right)$
C.
$\frac{1}{\sqrt{2\gamma g}}\tan^{-1}\left(\sqrt{\frac{2\gamma}{g}}V_{0}\right)$
D.
$\frac{1}{\sqrt{\gamma g}}\ln\left(1+\sqrt{\frac{\gamma}{g}}V_{0}\right)$
JEE (Main) 2019 Q112 Allen JEE Main PYQ MCQ
A spring whose unstretched length is $l$ has a force constant $k$ . The spring is cut into two pieces of unstretched lengths $l_{1}$ and $l_{2}$ where, $l_{1} = nl_{2}$ and $n$ is an integer. The ratio $k_{1}/k_{2}$ of the corresponding force constants, $k_{1}$ and $k_{2}$ will be :
A.
$\frac{1}{n^2}$
B.
$n^2$
C.
$\frac{1}{n}$
D.
$n$
JEE (Main) Jan. 2019 Q113 Errorless Critical Thinking MCQ
A mass of 10 kg is suspended vertically by a rope from the roof. When a horizontal force is applied on the rope at some point, the rope deviated at an angle of $45^{\circ}$ at the roof point. If the suspended mass is at equilibrium, the magnitude of the force applied is $(g = 10 \, ms^{-2})$
A.
200 N
B.
100 N
C.
140 N
D.
70 N
JEE (Main) Jan. 2019 Q114 Errorless Critical Thinking MCQ
A block of mass 10 kg is kept on a rough inclined plane as shown in the figure. A force of 3 N is applied on the block. The coefficient of static friction between the plane and the block is 0.6. What should be the minimum value of force P, such that the block does not move downward (Take $g = 10 ms^{-2}$ )
A.
$32N$
B.
$25N$
C.
23 N
D.
18N
JEE (Main) Jan. 2019 Q115 Errorless Critical Thinking MCQ
A particle of mass m is moving in a straight line with momentum p. Starting at time t=0, a force F=kt acts in the same direction on the moving particle during time interval T so that its momentum changes from p to 3p. Here k is a constant. The value of T is
A.
$2\sqrt{\frac{p}{k}}$
B.
$\sqrt{\frac{2p}{k}}$
C.
$\sqrt{\frac{2k}{p}}$
D.
$2\sqrt{\frac{k}{p}}$
JEE (Main) April 2019 Q116 Errorless Critical Thinking MCQ
A bullet of mass 20 g has an initial speed of $1ms^{-1}$ , just before it starts penetrating a mud wall of thickness 20 cm. If the wall offers a mean resistance of $2.5 \times 10^{-2}N$ , the speed of the bullet after emerging from the other side of the wall is close to
A.
$0.4 ms^{-1}$
B.
$0.1 ms^{-1}$
C.
$0.3 ms^{-1}$
D.
$0.7 ms^{-1}$
JEE (Main) April 2019 Q117 Errorless Critical Thinking MCQ
A man (mass = 50 kg) and his son (mass = 20 kg) are standing on a frictionless surface facing each other. The man pushes his son so that he starts moving at a speed of $0.70 \, ms^{-1}$ with respect to the man. The speed of the man with respect to the surface is
A.
$0.20 \, ms^{-1}$
B.
$0.14 \, ms^{-1}$
C.
$0.47 \, ms^{-1}$
D.
$0.28 \, ms^{-1}$
JEE (Main) April 2019 Q118 Errorless Graphical Questions MCQ
A ball is thrown vertically up (taken as +z-axis) from the ground. The correct momentum-height $(p-h)$ diagram is
A.
B.
C.
D.
JEE (Advanced) 2019 Q119 Errorless JEE Section MCQ
A block of mass 2M is attached to a massless spring with spring-constant k. This block is connected to two other blocks of masses M and 2M using two massless pulleys and strings. The accelerations of the blocks are $a_{1}$ , $a_{2}$ and $a_{3}$ as shown in figure. The system is released from rest with the spring in its unstretched state. The maximum extension of the spring is $x_{0}$ . Which of the following option(s) is/are correct [g is the acceleration due to gravity. Neglect friction]
A.
$x_0 = \frac{4Mg}{k}$
B.
When spring achieves an extension of $\frac{x_{0}}{2}$ for the first time, the speed of the block connected to the spring is $3g\sqrt{\frac{M}{5k}}$
C.
$a_{2} - a_{1} = a_{1} - a_{3}$
D.
At an extension of $\frac{x_0}{4}$ of the spring, the magnitude of acceleration of the block connected to the spring is $\frac{3g}{10}$
JEE (Main) Jan. 2019 Q120 Errorless Critical Thinking-friction MCQ
A block kept on a rough inclined plane, as shown in the figure, remains at rest up to a maximum force $2N$ down the inclined plane. The maximum external force up the inclined plane that does not move the block is $10N$ . the coefficient of static friction between the block and the plane is [Take $g = 10m / s^2$ ]
A.
$\frac{2}{3}$
B.
$\frac{\sqrt{3}}{2}$
C.
$\frac{\sqrt{3}}{4}$
D.
$\frac{1}{2}$
JEE (Main) April 2019; March/Aug. 2021, June 2022 Q121 Errorless Critical Thinking-friction MCQ
Two blocks A and B of masses $m_{A}=1kg$ and $m_{B}=3kg$ are kept on the table as shown in figure. The coefficient of friction between A and B is 0.2 and between B and the surface of the table is also 0.2. The maximum force F that can be applied on B horizontally. So that the block A does not slide over the block B is [Take $g = 10m / s^2$ ]
A.
16 N
B.
40 N
C.
12 N
D.
8 N
JEE (Main) April 2019 Q122 Errorless Critical Thinking-friction MCQ
A block of mass 5 kg is (i) pushed in case (A) and (ii) pulled in case (B), by a force F=20 N, making an angle of $30^{\circ}$ with the horizontal, as shown in the figures. The coefficient of friction between the block and floor is $\mu=0.2$ . The difference between the accelerations of the block, in case (B) and case (A) will be: $(g=10\ ms^{-2})$

(A)

(B)
A.
$0ms^{-2}$
B.
$0.8ms^{-2}$
C.
$0.4ms^{-2}$
D.
$3.2ms^{-2}$
Online April 2019 Q123 Advance ARCHIVE: JEE MAIN MCQ
If $10^{22}$ gas molecules each of mass $10^{-26}$ kg collide with a surface (perpendicular to it) elastically per second over an area $1\mathrm{m}^2$ with a speed $10^{4}\mathrm{ms}^{-1}$ , the pressure exerted by the gas molecules will be of the order of
A.
$1\mathrm{Nm}^{-2}$
B.
$2\mathrm{Nm}^{-2}$
C.
$3\mathrm{Nm}^{-2}$
D.
$4\mathrm{Nm}^{-2}$
Online April 2019 Q124 Advance ARCHIVE: JEE MAIN MCQ
A ball is thrown vertically up (taken as +z-axis) from the ground. The correct momentum height $(p-h)$ diagram is
A.
B.
C.
D.
Online April 2019 Q125 Advance ARCHIVE: JEE MAIN MCQ
A ball is thrown upward with an initial velocity $V_{0}$ from the surface of the earth. The motion of the ball is affected by a drag force equal to $m\gamma v^{2}$ (where m is mass of the ball, v is its instantaneous velocity and $\gamma$ is a constant). Time taken by the ball to rise to its zenith is
A.
$\frac{1}{\sqrt{\gamma g}}\sin^{-1}\left(\sqrt{\frac{\gamma}{g}} V_0\right)$
B.
$\frac{1}{\sqrt{\gamma g}}\ln \left(1 + \sqrt{\frac{\gamma}{g}} V_0\right)$
C.
$\frac{1}{\sqrt{\gamma g}}\tan^{-1}\left(\sqrt{\frac{\gamma}{g}}V_{0}\right)$
D.
$\frac{1}{\sqrt{2\gamma g}}\tan^{-1}\left(\sqrt{\frac{2\gamma}{g}} V_0\right)$