List of top Physics Questions

In a closed organ pipe, the first resonance occurs at $50\, cm$. At what length of pipe, the second resonance will occur?
Two identical cells each of emf E and internal resistance r are connected in parallel with an external resistance R. To get maximum power developed across R, the value of R is
An object is placed at a distance of $40\, cm$ in front of a concave mirror of focal length $20\, cm$. The nature of image is
An AC voltage is applied to a pure inductor $L$, drives a current in the inductor. The current in the inductor would be
Nichrome or Manganin is widely used in wire bound standard resistors because of their
Two metallic rings $A$ and $B$, identical in shape and size but having different resistivities $\rho_A \, and \, \rho_B$, are kept on top of two identical solenoids as shown in the figure. When current $I$ is switched on in both the solenoids in identical manner, the rings $A$ and $B$ jump to heights $h_A \, and \, h_B$, respectively, with $h_A > h_B$. The possible relation(s) between their resistivities and their masses $m_A$ and $m_B$ is (are)
Read the following statements $S _{1}:$ An object shall weigh more at pole than at equator when weighed by using a physical balance. $S _{2}$ : It shall weigh the same at pole and equator when weighed by using a physical balance. $S _{3}$ : It shall weigh the same at pole and equator when weighed by using a spring balance. $S _{4}$ : It shall weigh more at the pole than at equator when weighed using a spring balance. Which of the above statements is/are correct?
If a sphere is rolling, the ratio of its rotational energy to the total kinetic energy is given by
Two small and heavy spheres, each of mass $M$, are placed a distance $r$ apart on a horizontal surface. The gravitational potential at the mid-point on the line joining the centre of the spheres is
Two springs $A$ and $B$ are identical but $A$ is harder than $B\left(k_{A} >k_{B}\right)$. Let $W_{A}$ and $W_{B}$ represent the work done when the springs are stretched through the same distance and $W_{A}'$ and $W_{B}'$ are the work done when these are stretched by equal forces, then which of the following is true?
Identify the wrong statement.
In the rectangular lamina shown in the figure, $ AB=\frac{BC}{2}. $ The moment of inertia of the lamina is minimum along the axis passing through
Ten one- rupee coins are put on top of each other on a table. Each coin has a mass $m$. Which of the following statements is not true?
Pure silicon at 300 K has equal electron (n$_e$) and hole (n$_h$) concentration of $1.5 \times 10^{16} m^{-3}$. Doping by indium increases $n_h$ to $4.5 \times 10^{22}m^{-3}$ The $n_e $ in the doped silicon is
A $10\, kg$ stone is suspended with a rope of breaking strength $30 \,kg - wt$. The minimum time in which the stone can be raised through a height $10\, m$ starting from rest is (Taking $g =10 \,N\,kg ^{-1}$ )
If the force acting on a body is inversely proportional to its speed, then its kinetic energy is
In inelastic collision
A sphere is rolling without slipping on a fixed horizontal plane surface In the figure, A is the point of contact. B is the centre of the sphere and C is its topmost point. Then,
C$_v$ and C$_p$ denote the molar specific heat capacities of a gas at constant volume and constant pressure, respectively. Then,
Ablockofbase $l0 cm\times10 cm$ and height 15 cm is kept on an inclined plane. The coefficient of friction between them is $\sqrt3$. The inclination $\theta$ of this inclined plane from the horizontal plane is gradually increased from 0$^{\circ}$. Then
A student performed the experiment to measure the speed of sound in air using resonance air-column method. Two resonances in the air-column were obtained by lowering the water level. The resonance with the shorter air-column is the first resonance and that with the longer air column is the second resonance. Then,
A ball is dropped from a height of $20\, m$ above the surface of water in a lake. The refractive index of water is$\frac{4}{3}$ A fish fish inside the lake, in the line of fall of the ball, is looking at the ball. At an instant, when the ball is 12.8 m above the water surface, the fish sees the speed of ball as ($Take g = 10\,m/s^2$)
Diwali rocket is ejecting $50\, g$ of gasses at a velocity of $400 \,m/s$ . The accelerating force on the rocket will be
A symmetric double convex lens is cut in two equal parts by a plane perpendicular to the principal axis. If the power of the original lens is $4\,D$ , the power of a cut lens will be
In radioactive decay process, the negatively charged emitted $\beta-$ particles are