List of top Physics Questions

As per this diagram a point charge +q is placed at the origin O. Work done in taking another point charge -Q from the point A [co-ordinates (0,a)] to another point B [coordinates (a,0)] along the straight path AB is:
 

A solid cylinder rolls down an inclined plane of height 3 m and reaches the bottom of plane with angular velocity, of 2 $ \sqrt {2} rads ^{-1} $ . The radius of cylinder must be (Take g = 10 $ ms ^{-2}$ )

A wire of natural length $ l, $ Youngs modulus $ Y $ and area of cross-section $ A $ is extended by $ x $ . Then the energy stored in the wire is given by

A transverse wave is described by the equation $ y={{y}_{0}}\sin 2\pi \left( ft-\frac{x}{\lambda } \right). $ The maximum particle velocity is equal to four times the wave velocity, if

After terminal velocity is reached, the acceleration of a body falling through a fluid is

A ray of light passes through an equilateral prism such that an angle of incidence is equal to the angle of emergence and the latter is equal to $ \frac{3}{4} $ th the angle of prism. The angle of deviation is:

If the unit of force and length are doubled, the unit of energy will be

A stone falls freely from rest from a height $h$ and it travels a distance $\frac{9h}{25}$ in the last second. The value of $h$ is

A particle of mass m is moving along the x-axis under the potential $V (x) = \frac{kx^2}{2} + \frac{\lambda}{x}$, where $k $ and $\lambda$ are positive constants of appropriate dimensions. The particle is slightly displaced from its equilibrium position. The particle oscillates with the angular frequency $\omega$ given by

A particle of mass $m$ and charge $q$ with an initial velocity $v$ is subjected to a uniform magnetic field $B$ along the vertical direction. The particle will

Identify the mismatched pair from the following

An electric dipole consists of two opposite charges each 0.05 $\mu$C separated by 30 mm. The dipole is placed in an uniform external electric field of $ 10^6 \, NC^{ - 1}$. The maximum torque exerted by the field on the dipole is

A voltage $V_{PQ} = V_0 \, \cos \, \omega t$ (where $V_0$ is a real amplitude) is applied between the points P and Q in the network shown in the figure. The values of capacitance and inductance are $C = \frac{1}{\omega R \sqrt{3}}$ and $L = \frac{R \sqrt{3}}{\omega}$ Then, the total impedance between P and Q is

For signal transmission, modulation is necessary

Two planets have radii $r_1$ and $r_2$ and densities $d_1$ and $d_2$ respectively. Then the ratio of accelerations due to gravity on them is

The length of a rubber cord is $ {{l}_{1}} $ metre when the tension is $ 4\, N $ and $ {{l}_{2}} $ metre when the tension is $ 6\, N $ . The length when the tension is $9\,N$, is

A pendulum of length 1 m is released from $\theta$ = 60$^{\circ}$. The rate of change of speed of the bob at $\theta$= 30$^{\circ}$ is $(g=10 \, ms^{-1})$

A tank is filled with water of density $1\frac{g}{{cm}^3}$ and oil of density $0.9\frac{g}{{cm}^3}$. The height of water layer is $100cm$ and that of oil layer is 400 $cm$. If $g=980\frac{cm}{s^2}$, then the velocity of efflux from an opening in the bottom of the tank will be-

When a ceiling fan is switched off, its angular velocity reduces to half its initial value after it completes 36 rotations. The number of rotations it will make further before coming to rest is (Assuming angular retardation to be uniform)

Two identical objects each of mass $50 \,kg$ are kept at a distance of separation of $50\, cm$ apart on a horizontal table. The net gravitational force at the mid-point of the line joining their centres is

Which one of the following is SHM?

When a same force of 5 N is applied to two balls A and B separately, they move along the direction of the force with a velocity of 5 ms and 10 ms respectively. The rate of work done on the ball A to that on B are in the ratio

Water flows through a horizontal pipe of diameter $2 \,cm$ at a speed of $3 \,cm \,s^{-1}$, The pipe has a nozzle of diameter $0.5 \,cm$ at its end. The speed of water emerging from the nozzle is

A $240V,60Hz$ voltage source is connected to resistor of $60\mathrm{\Omega }$. Find the value of net power consumed by resistance over a complete cycle.

Certain amount of heat is given to 100 g of copper to increase its temperature by 21 $^{\circ}$C. if the same amount of heat is given to 50 g of water, then the rise in its temperature is (specific heat capacity of copper = 400 Jkg$^{-1} K^{-1}$ and that for water =4200Jkg$^{-1}ZK^{-1}$