List of top Physics Questions

The uncertainty in the velocities of two particles \( A \) and \( B \) are \( 0.03 \) and \( 0.01 \, \text{m/s} \), respectively. The mass of \( B \) is four times the mass of \( A \). The ratio of uncertainties in their positions is:
Ionosphere acts as a reflector for the frequency range of

If three logic gates are connected as shown in the figure, then the correct truth table of the circuit is

 

In a common emitter amplifier of a transistor, if the ratio of the voltage gain and current amplification factor is 4, then the ratio of the collector and base resistances is.
The density (in \( \text{kg m}^{-3} \)) of nuclear matter is of the order of
The waves having maximum wavelength among the following electromagnetic waves is
In a series resonant LCR circuit, for the power dissipated to become half of the maximum power dissipated, the current amplitude is
A solenoid of one meter length and \( 3.55 \, \text{cm} \) inner diameter carries a current of \( 5 \, A \). If the solenoid consists of five closely packed layers each with \( 700 \) turns along its length, then the magnetic field at its centre is
A DC supply of \(160\,V\) is used to charge a battery of EMF \(10\,V\) and internal resistance \(1\,\Omega\) by connecting a series resistance of \(24\,\Omega\). The terminal voltage of the battery during charging is:
The work done by 6 moles of helium gas when its temperature increases by \( 20^\circ \text{C} \) at constant pressure is (Universal gas constant = \( 8.31 \, \text{J mol}^{-1} \, \text{K}^{-1} \))

The coordinates of the centre of mass of a uniform L-shaped plate of mass 3 kg shown in the figure is:

 

If a force of \( (6x^2 - 4x) \, \text{N} \) acts on a body of mass 10 kg, then the work to be done by the force in displacing the body from \( x = 2 \, \text{m} \) to \( x = 4 \, \text{m} \) is
Water flowing through a pipe of area of cross-section \( 2 \times 10^{-3} \, \text{m}^2 \) hits a vertical wall horizontally with a velocity of \( 12 \, \text{m/s} \). If the water does not rebound after hitting the wall, then the force acting on the wall due to water is
A particle moving along a straight line covers the first half of the distance with a speed of \( 3 \, \text{m/s} \), the other half of the distance is covered in two equal time intervals with speeds of \( 4.5 \, \text{m/s} \) and \( 7.5 \, \text{m/s} \) respectively, then the average speed of the particle during the motion is
In a Carnot engine, if the absolute temperature of the source is \( 25% \) more than the absolute temperature of the sink, then the efficiency of the engine is
A force \( F \) is applied on a body of mass \( m \) so that the body starts moving from rest. The power delivered by the force at time \( t \) is proportional to:
In an LCR series circuit, if the potential differences across inductor, capacitor, and resistor are $60~\text{V}$, $30~\text{V}$, and $40~\text{V}$ respectively, then the net voltage applied to the circuit is
When a sphere is taken to the bottom of a sea of depth $1~\text{km}$, it contracts in volume by $0.01%$. Then the bulk modulus of the material of the sphere is (Acceleration due to gravity = $10~\text{m/s}^2$)
If five logic gates are connected as shown in the figure, then the values of $y_1$, $y_2$, and $y_3$ are respectively
logic gates
The difference between the frequencies of the first and second Lyman lines of hydrogen atom is (R - Rydberg constant and c - speed of light in vacuum)
Two concentric loops $A$ and $B$ of same radius $2\pi~\text{cm$ are placed at right angles to each other. If the currents flowing through $A$ and $B$ are $3~\text{A}$ and $4~\text{A}$ respectively, then the net magnetic field at their common center is}
A Carnot engine having efficiency $60%$ receives heat from a source at temperature $600~\text{K$. For the same sink temperature, to increase its efficiency to $80%$, the temperature of the source is}
When a wire of length $L$ clamped at one end is pulled by a force $F$ from the other end, its length increases by $L'$. If the radius and the applied force are halved, then the increase in its length is
Ratio of angular velocity of hour hand of a watch and the angular velocity of rotation of earth is
The bob of a simple pendulum of length $200~\text{cm}$ is released from horizontal position.
If $10%$ of its initial energy is lost to air resistance, then the speed of bob at the mean position is
(Acceleration due to gravity $= 10~\text{m/s}^2$)