List of practice Questions

A particle of mass m at rest is acted upon by a force P for a time t. Its kinetic energy after an intervals is
A quarter horse power motor runs at a speed of $600\, rpm$. Assuming $40\%$ efficiency the work done by the motor in one rotation will be
A body of mass $1 \,kg$ is rotating in a vertical circle of radius $1\,m$. What will be the difference in its kinetic energy at the top and bottom of the circle? (take $ g=10\,m{{s}^{-2}} $ )
A body of mass $2 \,kg$ has an initial velocity of $3\, m/s$ along $OE$ and it is subjected to a force of $4 \,N$ in a direction perpendicular to $OE$. The distance of body from $O$ after $4 \,s$ will be
A body of mass $2\, kg$ makes an elastic collision with another body at rest and continues to move in the original direction with one-fourth its original speed. The mass of the second body which collides with the first body is
A block of mass $5 \,kg$ is moving horizontally at a speed of $ 1.5\,m{{s}^{-1}} $ . A vertically upward force $5 N$ acts on it for $4 s$. What will be the distance of the block from the point where the force starts acting?
A body freely falling from the rest has a velocity v after his falls through a height h. The distance, it has to fall down further for its velocity becomes double, is
A car of mass $m$ moves in a horizontal circular path of radius $r \,m$. At an instant its speed is $v \,m/s$ and is increasing at a rate of $ a\,m/{{s}^{2}} $ . Then the acceleration of the car is
The velocity $v$ (in cm/s) of a particle is given in terms of time $t$ (in $s$) by the equation, $ v=at+\frac{b}{t+c} $ The dimensions of $a, b$ and $c$ are
A ball is projected from the ground at angle $ \theta $ with the horizontal. After Is it is moving at angle $45^\circ$ with the horizontal and after $2\, s$ it is moving horizontally. What is the velocity of projection of the ball?
An engine is moving on a circular path of radius $100\, m$ with a speed of $20\, m/s$. What will be the frequency observed by an observer standing stationary at the centre of circular path when the engine blows a whistle of frequency $500\, Hz$?
Isobaric modulus of elasticity is equal to
The work done by a particle moving with a velocity of $0.7\, c$ (where c is the velocity of light) in empty space free of electromagnetic field and far away from all matter is:
A block of mass 2 kg is kept on the floor. The coefficient of static friction is 0.4. If a force of 2.5 N is applied on the block as shown in the figure, the frictional force between the block and the floor will be
A boat carrying a number of large stones is floating in a water tank. What will happen to the water level if the stones are unloaded into water?
In Youngs double slit experiment, the spacing between the slits is $d$ and wave length of light used is $ 6000\,? $ . If the angular width of a fringe formed on a distant screen is $ 1{}^\circ , $ then value of $d$ is:
Two slits $4\, mm$ apart, are illuminated by light of wavelength $6000\, ?$. What will be the fringe width on a screen placed $2\, m$ from the slits?
If two waves represented by $ y_{1}=4\sin \,\omega t $ and $ y_{2}=3\sin \left( \omega t+\frac{\pi }{3} \right) $ interfere at a point. The amplitude of the resulting wave will be about
In Young's double slit experiment, slit separation is $0.6 \,mm$ and the separation between slit and screen is $1.2\, m$. The angular width is (the wavelength of light used is $4800\,? $
A light ray is incident normally on a plane mirror. The angle of reflection will be
In an artificial satellite, a space traveller tries to fill ink in a pen by dipping it in ink. The amount of ink filled in the pen as compared to the quantity of ink filled on the earths surface will be
A gas is compressed adiabatically till its temperature is doubled. The ratio of his final volume to its initial volume will be
Energy is being emitted from the surface of a black body at $ 127{}^\circ C $ at the rate of $ (1.0\times {{10}^{6}})/s{{m}^{2}} $ . The temperature of a black body at which the rate of energy emission is $ (16.0\times {{10}^{6}})/s{{m}^{2}} $ will be
A bar magnet of magnetic moment M is placed in the magnetic field B. The torque acting on the magnet is.
Of the diodes shown in the following diagrams, which one is reverse biased?