List of top Physics Questions

In a Screw Gauge, fifth division of the circular scale coincides with the reference line when the ratchet is closed. There are 50 divisions on the circular scale, and the main scale moves by 0.5 mm on a complete rotation. For a particular observation the reading on the main scale is 5 mm and the 20th division of the circular scale coincides with reference line. Calculate the true reading.
Two bodies of masses 8 kg are placed at the vertices A and B of an equilateral triangle ABC. A third body of mas 2 kg is placed at the centroid G of the triangle. If AG = BG = CG = 1 m, where should a fourth body of mass 4 kg be placed so that the resultant force on the 2 kg body is zero?
Which of the following waves are used in the treatment of muscle ache?
The displacement of a wave is given by \( y = 20 \cos(\omega t + 4x) \). The amplitude of the wave is
The function \( y = \log(\omega t) \) can represent
Radius of gyration of a solid cylinder of radius R and length L about its long axis of symmetry is

An object is placed at a distance of 12 cm from a convex lens. A convex mirror of focal length 15 cm is placed on other side of lens at 8 cm as shown in the figure. Image of object coincides with the object. When the convex mirror is removed, a real and inverted image is formed at a position. The distance of the image from the object will be __________ (cm). 

 

For the given circuit, the power across zener diode is __________ mW. 

 

A parallel-plate capacitor with plate area A has separation d between the plates. Two dielectric slabs of dielectric constant K\(_1\) and K\(_2\) of same area A/2 and thickness d/2 are inserted in the space between the plates. The capacitance of the capacitor will be given by: 

 

In the given circuit the AC source has \(\omega\) = 100 rad s\(^{-1}\). Considering the inductor and capacitor to be ideal, what will be the current I flowing through the circuit ? 

Two blocks of masses 3 kg and 5 kg are connected by a metal wire going over a smooth pulley. The breaking stress of the metal is \( \frac{24}{\pi} \times 10^2 \) Nm\(^{-2}\). What is the minimum radius of the wire ? 
(take g=10 ms\(^{-2}\)) 

 

The solid cylinder of length 80 cm and mass M has a radius of 20 cm. Calculate the density of the material used if the moment of inertia of the cylinder about an axis CD parallel to AB as shown in figure is 2.7 kg m\(^2\). 

 

The angle between vector \( (\vec{A}) \) and \( (\vec{A} - \vec{B}) \) is: 

 

At time t = 0, a material is composed of two radioactive atoms A and B, where N$_A$(0) = 2N$_B$(0). The decay constant of both kind of radioactive atoms is \(\lambda\). However, A disintegrates to B and B disintegrates to C. Which of the following figures represents the evolution of N$_B$(t)/N$_B$(0) with respect to time t? 
[ $N_A(0)$ = No. of A atoms at t = 0 ] 
[ $N_B(0)$ = No. of B atoms at t = 0 ] 

Four NOR gates are connected as shown in figure. The truth table for the given figure is : 

Match List - I with List - II : 

Choose the most appropriate answer from the options given below : 
 

Two waves are simultaneously passing through a string and their equations are :
\(y_1 = A_1 \sin k(x - vt), y_2 = A_2 \sin k(x-vt+x_0)\). Given amplitudes \(A_1 = 12\) mm and \(A_2 = 5\) mm, \(x_0=3.5\) cm and wave number \(k=6.28\) cm\(^{-1}\). The amplitude of resulting wave will be __________ mm.
A coil in the shape of an equilateral triangle of side 10 cm lies in a vertical plane between the pole pieces of permanent magnet producing a horizontal magnetic field 20 mT. The torque acting on the coil when a current of 0.2 A is passed through it and its plane becomes parallel to the magnetic field will be \( \sqrt{x} \times 10^{-5} \) Nm. The value of x is __________.
A circular coil of radius 8.0 cm and 20 turns is rotated about its vertical diameter with an angular speed of 50 rad s\(^{-1}\) in a uniform horizontal magnetic field of 3.0\( \times \)10\(^{-2}\) T. The maximum emf induced the coil will be __________ \( \times \)10\(^{-2}\) volt (rounded off to the nearest integer).
The coefficient of static friction between two blocks is 0.5 and the table is smooth. The maximum horizontal force that can be applied to move the blocks together is __________ N.
(take g=10 ms\(^{-2}\))
\includegraphics[width=0.5\linewidth]{21.png}
The two thin coaxial rings, each of radius 'a' and having charges +Q and -Q respectively are separated by a distance of 's'. The potential difference between the centres of the two rings is:
The acceleration due to gravity is found upto an accuracy of 4% on a planet. The energy supplied to a simple pendulum of known mass 'm' to undertake oscillations of time period T is being estimated. If time period is measured to an accuracy of 3%, the accuracy to which E is known as __________ %.
Two simple harmonic motions are represented by the equations \( x_1 = 5 \sin(2\pi t + \frac{\pi}{4}) \) and \( x_2 = 5\sqrt{2}(\sin(2\pi t) + \cos(2\pi t)) \). The amplitude of second motion is __________ times the amplitude in first motion.
A source of light is placed in front of a screen. Intensity of light on the screen is I. Two Polaroids P\(_1\) and P\(_2\) are so placed in between the source of light and screen that the intensity of light on screen is I/2. P\(_2\) should be rotated by an angle of __________ (degrees) so that the intensity of light on the screen becomes \(\frac{3I}{8}\).
If the maximum value of accelerating potential provided by a radio frequency oscillator is 12 kV. The number of revolution made by a proton in a cyclotron to achieve one sixth of the speed of light is __________.
[m\(_p\) = 1.67\( \times \)10\(^{-27}\) kg, e = 1.6\( \times \)10\(^{-19}\) C, Speed of light = 3\( \times \)10\(^8\) m/s]