JEE Main Physics — Mechanics previous year questions with solutions.
 A hydraulic press containing water has two arms with diameters as mentioned in the figure. A force of $10 \mathrm{~N}$ is applied on the surface of water in the thinner arm. The force required to be applied on the surface of water in the thicker arm to maintain equilibrium of water is _____N.
A train is moving with a speed of $12m{s}^{-1}$ on rails which are $1.5m$ apart. To negotiate a curve radius $400m$, the height by which the outer rail should be raised with respect to the inner rail is (Given, $g=$ $10m{s}^{-2}$):
A stone of mass $900g$ is tied to a string and moved in a vertical circle of radius $1m$ making $10\mathrm{rpm}$. The tension in the string, when the stone is at the lowest point is (if ${\pi }^{2}=9.8$ and $g=9.8m{s}^{-2}$)
If the radius of earth is reduced to three-fourth of its present value without change in its mass then value of duration of the day of earth will be ______ hours 30 minutes.
A $1 \mathrm{~kg}$ mass is suspended from the ceiling by a rope of length $4 \mathrm{~m}$. A horizontal force ' $F$ ' is applied at the mid point of the rope so that the rope makes an angle of $45^{\circ}$ with respect to the vertical axis as shown in figure. The magnitude of $F$ is : (Assume that the system is in equilibrium and $g=10 \mathrm{~m} / \mathrm{s}^2$ ) 
In a test experiment on a model aeroplane in wind tunnel, the flow speeds on the upper and lower surfaces of the wings are $70m{s}^{-1}$ and $65m{s}^{-1}$ respectively. If the wing area is $2{m}^{2}$, the lift of the wing is _______$N$. (Given density of air $=1.2\mathrm{kg}{m}^{-3}$)
A particle of mass $m$ projected with a velocity $u$ making an angle of $30^{\circ}$ with the horizontal. The magnitude of angular momentum of the projectile about the point of projection when the particle is at its maximum height $h$ is :
Mercury is filled in a tube of radius $2 \mathrm{~cm}$ up to a height of $30 \mathrm{~cm}$. The force exerted by mercury on the bottom of the tube is _____ N. (Given, atmospheric pressure $=10^5 \mathrm{Nm}^{-2}$, density of mercury $=1.36 \times 10^4 \mathrm{~kg} \mathrm{~m}^{-}$ $\left.{ }^3, \mathrm{~g}=10 \mathrm{~m} \mathrm{~s}^{-2}, \pi=\frac{22}{7}\right)$
If $\vec{a}$ and $\vec{b}$ makes an angle $\cos ^{-1}\left(\frac{5}{9}\right)$ with each other, then $|\vec{a}+\vec{b}|=\sqrt{2}|\vec{a}-\vec{b}|$ for $|\vec{a}|=n|\vec{b}|$ The integer value of $\mathrm{n}$ is ____
Match List - I with List - II.<br><table class="pyq-table"><tbody><tr><td colspan="2" rowspan="1">List - I (Number)</td><td colspan="2" rowspan="1">List - II (Signficant figure)</td></tr><tr><td>(A)</td><td>$1001$</td><td>(I)</td><td>$3$</td></tr><tr><td>(B)</td><td>$010.1$</td><td>(II)</td><td>$4$</td></tr><tr><td>(C)</td><td>$100.100$</td><td>(III)</td><td>$5$</td></tr><tr><td>(D)</td><td>$0.0010010$</td><td>(IV)</td><td>$6$</td></tr></tbody></table>Choose the correct answer from the options given below:
A particle moves in a circle of radius R with constant speed v. Its centripetal acceleration is
The dimension of Planck constant is same as
In a vernier calliper, when both jaws touch each other, zero of the vernier scale shifts towards left and its $4^{\text {th }}$ division coincides exactly with a certain division on main scale. If 50 vernier scale divisions equal to 49 main scale divisions and zero error in the instrument is $0.04 \mathrm{~mm}$ then how many main scale divisions are there in $1 \mathrm{~cm}$ ?
What is the maximum height attained by the ball perpendicular to the inclined surface?
What is the time of flight of the ball along the inclined plane?
A circular disc reaches from top to bottom of an inclined plane of length $l$. When it slips down the plane, if takes $t \mathrm{~s}$. When it rolls down the plane then it takes $\left(\frac{\alpha}{2}\right)^{1 / 2} t \mathrm{~s}$, where $\alpha$ is _________
The dimensional formula of latent heat is :
A light planet is revolving around a massive star in a circular orbit of radius $R$ with a period of revolution $T.$ If the force of attraction between planet and star is proportional to ${R}^{-3/2}$ then choose the correct option :
One end of a metal wire is fixed to a ceiling and a load of $2\mathrm{kg}$ hangs from the other end. A similar wire is attached to the bottom of the load and another load of $1\mathrm{kg}$ hangs from this lower wire. Then the ratio of longitudinal strain of upper wire to that of the lower wire will be [Area of cross section of wire $=0.005{\mathrm{cm}}^{2},Y=2\times {10}^{11}N{m}^{-2}$ and $g=10m{s}^{-2}$]
Four particles $A, B, C, D$ of mass $\frac{m}{2}, m, 2 m, 4 m$, have same momentum, respectively. The particle with maximum kinetic energy is :
Young's modules of material of a wire of length $L$ and cross-sectional area $A$ is $Y.$ If the length of the wire is doubled and cross-sectional area is halved then Young's modules will be:
A body of mass $5\mathrm{kg}$ moving with a uniform speed $3\sqrt{2}m{s}^{-1}$ in $X-Y$ plane along the line $y=x+4$. The angular momentum of the particle about the origin will be _______$\mathrm{kg}{m}^{2}{s}^{-1}$.
A man carrying a monkey on his shoulder does cycling smoothly on a circular track of radius $9 \mathrm{~m}$ and completes 120 resolutions in 3 minutes. The magnitude of centripetal acceleration of monkey is $\left(\right.$ in $\mathrm{m} / \mathrm{s}^2$ ) :
Given below are two statements : Statement (I) : Dimensions of specific heat is $\left[\mathrm{L}^2 \mathrm{~T}^{-2} \mathrm{~K}^{-1}\right]$. Statement (II) : Dimensions of gas constant is $\left[\mathrm{M} \mathrm{L}^2 \mathrm{~T}^{-1} \mathrm{~K}^{-1}\right]$. In the light of the above statements, choose the most appropriate answer from the options given below.