List of top Physics Questions

' $n$ ' polarizing sheets are arranged such that each makes an angle $45^{\circ}$ with the preceeding sheet An unpolarized light of intensity I is incident into this arrangement The output intensity is found to be $I / 64$ The value of $n$ will be:
The output Y for the inputs A and B of circuit is given by Truth table of the shown circuit is:
The output Y for the inputs A and B
An ice block floats in a liquid whose density is less than water. A part of block is outside the liquid. When whole of ice has melted, the liquid level will
When two resistors of resistances \( (123 \pm 2) \, \Omega \) and \( (227 \pm 4) \, \Omega \) are connected in series, then the value of equivalent resistance is:
Two bodies A and B are projected simultaneously with velocities \( 20 \, \text{ms}^{-1} \) and \( 40 \, \text{ms}^{-1} \), respectively. Body A is projected vertically up from the top of a tower of height 80 m and body B is projected vertically up from the bottom of the same tower. The bodies A and B meet in time of:
A light whose electric field vectors are completely removed by using a good polaroid, allowed to incident on the surface of the prism at Brewster’s angle. Choose the most suitable option for the phenomenon related to the prism.
If a closed organ pipe has the same third harmonic frequency as that of an open organ pipe, then their respective lengths are in the ratio
N fundamental charge each of charge q are to be distributed as two point charges separated by a .fixed distance, then the maximum to minimum force bears a ratio (N is even and greater than.2)

Two magnets of equal magnetic moment (\( m_1 = m_2 \)) are placed as shown in the figure. If the magnetic field intensity at P due to magnet A1 is \( 2 \times 10^{-3} \, \text{Tesla} \), then find out the total magnetic field intensity at P due to both the magnets. 
 

In a Silicon p-n junction diode, for 20 V forward voltage, the forward current produced is 10 mA. Calculate its forward resistance. 
 

 Find the current through the 10 Ω resistor when the switch S is open and closed in the given circuit.

Quantization of charge implies :
In the given system of three blocks, the surfaces are frictionless. The ratio T1/T2 is:
At a given place where acceleration due to gravity is ' 8′m/s2, a sphere of lead of density 'd' kg/m3 is gently released in a column of liquid of density ρkg/m3. If d>ρ, the sphere will
Two disks of equal mass but different diameter are connected with an axle system that allows them to roll down an inclined plane together. Both disks start and finish at the same time. Which of the following statements best describes the disks?
The value of F so as to keep the smooth wedge stationary, when it is loaded with a block of mass M, which is connected with a light inextensible string, will be
Two mirrors at an angle θº produce 5 images of a point. The number of images produced when θ is decreased to θº – 30º is
Narrow capillary tubes A and B are of length l and l/2 and of the same radius r. The rate of flow of water through the tube A under a constant pressure head 'P' is 3 cm3/sec. If A and B are connected in series and the same pressure difference 'P' is maintained between the ends of the composite tube, then the rate of flow of water is
A parachutist, after bailing out, falls 50 m without friction. When parachute opens, it retards at 2 ms-2. He reaches the ground with a speed of 3 ms-1. At what height did he bail out?
A copper bar of length 1 m and cross-sectional area 10 × 10-2 m2 has its one end maintained at 100oC by means of 0.4 kW electric heater. What is the temperature of the other end in steady state, given that the thermal conductivity of copper is 400 W/mK?
A proton is projected with a velocity 107 ms-1 at right angles to a uniform magnetic field of induction 100 mT. The time (in seconds) taken by the proton to traverse 90o arc is(Mass of proton = 1.65 × 10-27 kg and charge of proton = 1.6 × 10-19 C)
A conducting sphere of radius R, carrying charge Q, lies inside an uncharged conducting shell of radius 2R. If they are joined by a metal wire, then
The equation of transverse wave is given by y=5sin⁡2π(t0.04−x40), where distance is in cm and time insecond. The wavelength of wave will be
A small ball is connected to a block by a light string of length L. Both are initially on the ground. There is sufficient friction on the ground to prevent the block from slipping. The ball is projected vertically upwards with a velocity u, where 2gl < u2 < 3gl. The centre of mass of the 'block + ball' system is C. Then,
The temperature of an ideal gas is increased from 120 K to 480 K. If at 120 K, the root mean square speed of gas molecules is v, then at 480 K it will be