List of top Physics Questions

A Wheatstone bridge is initially at room temperature and all arms of the bridge have same value of resistances \[ (R_1=R_2=R_3=R_4). \] When \(R_3\) resistance is heated, its resistance value increases by \(10%\). The potential difference \((V_a-V_b)\) after \(R_3\) is heated is _______ V.

The speed of a longitudinal wave in a metallic bar is \(400\,\text{m/s}\). If the density and Young’s modulus of the bar material increase by \(0.5%\) and \(1%\) respectively, then the speed of the wave is changed approximately to _______ m/s.

An infinitely long straight wire carrying current $I$ is bent in a planar shape as shown in the diagram. The radius of the circular part is $r$. The magnetic field at the centre $O$ of the circular loop is : 
 

A block of mass \(5\) kg is moving on an inclined plane which makes an angle of \(30^\circ\) with the horizontal. The coefficient of friction between the block and the inclined plane surface is \(\dfrac{\sqrt{3}}{2}\). The force to be applied on the block so that the block moves {down the plane without acceleration is ________ N. (\( g = 10 \, \text{m s}^{-2} \))}

Three parallel plate capacitors each with area \(A\) and separation \(d\) are filled with two dielectric (\(k_1\) and \(k_2\)) in the following fashion. (\(k_1>k_2\)) Which of the following is true? 

A uniform bar of length \(12\,\text{cm}\) and mass \(20m\) lies on a smooth horizontal table. Two point masses \(m\) and \(2m\) are moving in opposite directions with the same speed \(v\) and in the same plane as the bar, as shown in the figure. These masses strike the bar simultaneously and get stuck to it. After collision the entire system is rotating with angular frequency \(\omega\). The ratio of \(v\) and \(\omega\) is
Block sliding down... moving up... distance S before stopping is _____.
A simple pendulum has a bob with mass \(m\) and charge \(q\). The pendulum string has negligible mass. When a uniform and horizontal electric field \( \vec{E} \) is applied, the tension in the string changes. The final tension in the string, when pendulum attains an equilibrium position is _______.
(\( g \): acceleration due to gravity)
In a double slit experiment the distance between the slits is 0.1 cm and the screen is placed at 50 cm from the slits plane. When one slit is covered with a transparent sheet having thickness t and refractive index n(=1.5), the central fringe shifts by 0.2 cm. The value of t is_________ cm.
Two resistors of $100\,\Omega$ each are connected in series with a $9\,\text{V}$ battery. A voltmeter of $400\,\Omega$ resistance is connected to measure the voltage drop across one of the resistors. The voltmeter reading is ___ V.
Which one of the following is not a measurable quantity?

The strain-stress plot for materials A, B, C and D is shown in the figure. Which material has the largest Young's modulus? 

Consider two identical metallic spheres of radius $R$ each having charge $Q$ and mass $m$. Their centers have an initial separation of $4R$. Both the spheres are given an initial speed of $u$ towards each other. The minimum value of $u$, so that they can just touch each other is :
(Take $k = \frac{1}{4 \pi \epsilon_0}$ and assume $kQ^2>Gm^2$ where $G$ is the Gravitational constant)
A vehicle moving at 36 km/hr is to be stopped by applying brakes in the next 5 m. If the vehicle weighs 2000 kg, determine the average force that must be applied on it.
The velocity and acceleration of a particle performing simple harmonic motion have a steady phase relationship. The acceleration shows a phase lead over the velocity in radians of
When a magnetic field is applied on a stationary electron, it
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
Consider a convex lens made of material of refractive index \( n = \frac{3}{2} \) and radius of curvature \( R \). What is the relation between focal length and radius?
A pure inductor of inductance \( 0.1 \, \text{H} \) is connected to an AC source (of rms voltage 220 V and angular frequency 300 Hz). The rms current is
Refer to the circuit diagram given below. The heat generated across the $6\ \Omega$ resistance in 100 second is $\frac{\alpha}{100}\ J$. The value of $\alpha$ is ________. (Nearest integer)
In YDSE, when light of wavelength 700nm is used, a fringe width of 0.5mm is obtained. What happens when light of wavelength 500nm is used?
A ball is thrown upwards with a velocity of \(20\,m/s\). Find the maximum height reached \((g=10\,m/s^2)\).
In a Wheatstone Bridge, all four arms have equal resistance of 1 \(\Omega\) each. A battery is connected across the bridge, and a galvanometer is connected between the middle junctions. What is the current flowing through the galvanometer?
Magnitude and direction of acceleration changes for:
What happens to a ferromagnetic material when its temperature is raised above Curie temperature?