List of top Physics Questions

A wire of mass \(100\,\text{g}\) is carrying a current of \(2\,\text{A}\) towards increasing \(x\) in the form \(y = x^2 \;(-2\,\text{m} \le x \le +2\,\text{m})\). This wire is placed in a magnetic field \(\vec{B} = -0.02\,\hat{k}\,\text{tesla}\). The acceleration of the wire (in \( \text{m s}^{-2} \)) is:
Modern vacuum pumps can evacuate a vessel down to a pressure of \(4.0 \times 10^{-15}\,\text{atm}\). At room temperature (300 K), taking \(R = 8.3\,\text{J K}^{-1}\text{mol}^{-1}\) and \(N_{\text{Avogadro}} = 6 \times 10^{23}\,\text{mol}^{-1}\), the mean distance between molecules of gas in an evacuated vessel will be of the order of:
Three concentric conducting shells carry charges +4Q on inner, –2Q on middle and +6Q on outer. The charge on inner surface of the outer shell is
Find equivalent capacitance between points A and B. Assume each conducting plate has same dimensions and neglect the thickness of plate. It is given that \[ \frac{6A\varepsilon_0}{d}=7\,\mu F, \] where A is the area of plates.
When an electric heater is switched on, the current \(i\) is plotted against time \(t\). Taking into account the variation of resistance with temperature, which of the following best represents the resulting curve?
The real angle of dip at a place, if a magnet is suspended at an angle of \(30^\circ\) to the magnetic meridian and the dip needle makes an angle of \(45^\circ\) with the horizontal, is:
In the indicator diagram fig. shown of Carnot cycle Ta, Tb, Te, Td represent temperature of gas at A, B, C, D respectively. Which of the following is correct relation
In the arrangement, spring constant \(k=2\) N/m, masses \(M=3\) kg and \(m=1\) kg, friction coefficient 0.1. Amplitude is 10 cm. The time period of SHM will be
A wire of variable mass per unit length is \( \mu = \mu_0 x \), hanging from the ceiling as shown in the figure. A small transverse disturbance is produced at its lower end. Find the time after which the disturbance will reach to the other end.
If gravitational acceleration at surface is \(g\), increase in P.E. lifting mass \(m\) to height equal to half radius \(R/2\) from surface will be
Temperature of body falls from 62°C to 50°C in 10 minutes. Surroundings are 26°C. The temperature after next 10 minutes will become
A cubical ball is taken to a depth of 200 m in sea. The decrease in volume observed is 0.1%. The bulk modulus of the ball is
Acceleration versus velocity graph of a particle moving in a straight line is as shown in the graph. The corresponding velocity–time graph would be
A man wishes to cross the river flowing with velocity \(v\) making angle \(\theta\) with y direction. If he swims with speed \(u\) and width of river is \(d\), the time taken will be
Four spheres of diameter 2a and mass m are placed on corners of square of side b. The moment of inertia of system about an axis through one side is
Time dependence of quantity \(P=P_0 e^{-a t^2}\), dimension of a is
In a system, 8 kg mass is subjected to a force of 16 N along positive y axis and another 8 N along positive x axis. The angle made by acceleration of centre of mass with x axis is
A mass \(m\) moves with velocity \(v\) and collides elastically with another identical mass. After collision, the first mass moves with velocity \(\frac{v}{\sqrt3}\) in a direction perpendicular to the initial direction of motion. Find the speed of 2nd mass after collision.
A lift is moving in upward direction. The total mass of the lift and the passengers is 1600 kg. The variation of the velocity of lift is as shown in the figure. The tension in the rope at \(t = 8^{\text{th}}\) second will be

 How much charge is there on a hole? Draw the circuit symbol of p-n junction diode. 
 

A vessel contains hydrogen and nitrogen gases in the ratio 2:3 by mass. If the temperature of the mixture of the gases is 30°C, then the ratio of the average kinetic energies per molecule of hydrogen and nitrogen gases is:
A circular plate of radius \( r \) is removed from a uniform circular plate P of radius \( 4r \) to form a hole. If the distance between the centre of the hole formed and the centre of the plate P is \( 2r \), then the distance of the centre of mass of the remaining portion from the centre of the plate P is?
The maximum height attained by the projectile is increased by 10% by keeping the angle of projection constant. What is the percentage increase in the time of flight?
A solid cylinder rolls down on an inclined plane of height \( h \) and inclination \( \theta \). The speed of the cylinder at the bottom is:

In the given circuit, if the potential at point B is 24 V, the potential at point A is: