List of top Physics Questions

What proves that light is a transverse wave?
The primary of a transformer has 400 turns while the secondary has 2000 turns. If the power output from the secondary at 1000 V is 12 kW, what is the primary voltage?
If the X-ray tube is working at 20 kV then the minimum wavelength of X-rays will be
Find error in calculation of resistivity of R = 65 ? 1 O l = 5 ? 0.1 mm d = 10 ? 0.5 mm
Two concentric circular coil of radius 20 cm and 30 cm carries current of 2A and 3A respectively in opposite direction then magnetic field at centre will be :-
Due to ? decay, what is the effect on neutron and proton numbers?
A particle is thrown vertically up with speed 6 m/s. Find maximum height achieved.
Find pressure on swimmer at a depth of 10 m in water.
The magnitude of point charge due to which the electric field 30 cm away has the magnitude ,$2 \, NC^{-1}$ will be
An object is placed at a distance of 20 cm from the pole of a concave mirror of focal length 10 cm. The distance of the image formed is
A step-up transformer operates on a 230 V line and a load current of 2 A. The ratio of primary and secondary windings is 1 : 25. Then the current in the primary is
A man weighing 60 kg is in a lift moving down with an acceleration of $1.8 \, ms^{-2}$. The force exerted by the floor on him is
A jet plane having a wing-span of 25 m is travelling horizontally towards east with a speed of 3600 km/hour. If the Earth?s magnetic field at the location is $4 \times 10^{-4} \, T$ and the angle of dip is $30^{\circ}$, then, the potential difference between the ends of the wing is
A cyclotron?s oscillator frequency is 10 MHz and the operating magnetic field is 0.66 T. If the radius of its dees is 60 cm, then the kinetic energy of the proton beam produced by the accelerator is
A space station is at a height equal to the radius of the Earth. If $'v_E'$ is the escape velocity on the surface of the Earth, the same on the space station is ....... times $v_E$.
The radius of the Earth is 6400 km. If the height of an antenna is 500 m, then its range is
In the circuit shown in the figure, the input voltage $V_i$ is $20 \, V , V_{BE} = 0 $ and $V_{CE} = 0$ .The values of $I_B , I_C$ and $\beta$ are given by
In a $p-n$ junction diode, change in temperature due to heating
If the mass of the Sun were ten times smaller and the universal gravitational constant were ten times larger in magnitude, which of the following is not correct ?
A solid sphere is rotating freely about its symmetry axis in free space. The radius of the sphere is increased keeping its mass same. Which of the following physical quantities would remain constant for the sphere ?
A solid sphere is in rolling motion. In rolling motion a body possesses translational kinetic energy $(K_t)$ as well as rotational kinetic energy , $(K_r)$ simultaneously. The ratio $K_t : (K_t + K_r)$ for the sphere is
A body initially at rest and sliding along a frictionless track from a height $h$ (as shown in the figure) just completes a vertical circle of diameter $AB \,=\, D$. The height h is equal to
A radioactive nucleus $A$ with a half-life $T$, decays into a nucleus $B$. At $t = 0$, there is no nucleus $B$. At sometime t, the ratio of the number of $B$ to that of $A$ is $0.3$. Then, $t$ is given by :
A capacitance of $2 \, \mu F$ is required in an electrical circuit across a potential difference of $1.0\, kV$. A large number of $1 \, \mu F$ capacitors are available which can withstand a potential difference of not more than $300\, V$. The minimum number of capacitors required to achieve this is :
When a current of $5 \,mA$ is passed through a galvanometer having a coil of resistance $15 \, \Omega$, it shows full scale deflection. The value of the resistance to be put in series with the galvanometer to convert it into a voltmeter of range $0-10 \,V$ is :