List of top Physics Questions

In a common base configuration; (transistor circuit) $I_E=1 mA,I_C =0.95 mA$. The value of base current is

In a car lift compressed air exerts a force $F_1$ on a small piston having a radius of 5cm. This pressure is transmitted to a second piston of radius 15cm. If the mass of the car to be lifted is 1350 kg. What is $F_1$ ?

In a ballistics demonstration a police officer fires a bullet of mass $50 \,g$ with speed $200\, ms^{-1}$ on soft plywood of thickness $2 \,cm$. The bullet emerges with only $10\%$ of its initial kinetic energy. The emergent speed of the bullet is

Impedance of the circuit shown below is

Imagine a system of units in which the unit of mass is $10\, kg$, length is $1 \,km$ and time is $1 \,min$. Then 1 joule in this system is equal to

Imagine an atom made up of a proton and a hypothetical particle of double the mass of the electron but having the same charge as the electron. Apply the Bohr atom model and consider all possible transitions of this hypothetical particle to the first excited level. The longest wavelength photon that will be emitted has wavelength $\lambda$ (given in terms of Rydberg constant R for the hydrogen atom) equal to

If $Z=\frac{A^{4}\,B^{1/3}}{CD^{3/2}}$. and $\Delta A$, $\Delta B$, $\Delta C$, and $\Delta D$ are their absolute errors in $A$, $B$, $C$ and $D$ respectively. The relative error in $Z$ is

If Young's modulus of iron be $2 \times 10^{11}N/m^{-2}$ and interatomic distance be $3 \times10^{-10}m^{-2}$, the interatomic force constant will be

If work is done on a system, depends upon initial and final positions only it can be due to

If we add two vectors of equal magnitudes but in opposite directions, we get

If $ W_{1} $ be the work to be done to form a bubble of volume $ V $ from a given solution. The work required to be done to form a bubble of volume $ 2 V $ is

If unit vectors $\hat{A}$ and $\hat{B}$ are inclined at an angle $\theta$, then $\left|\hat{A}-\hat{B}\right|$ is

If u represents object distance from pole of spherical mirror and $v$represents image distance from pole of mirror and f is the focal length of the mirror, then a straight line u = $v$ will,cut u versus $v$ graph at

If two identical bar magnets, each of length I , pole strength m and magnetic momen M are placed perpendicular to each other with their unlike poles in contact, the magnetic moment of the combination is

If three particles of masses 2kg, 1kg and 3 kg are placed at comers of an equilateral triangle of perimeter 6m then the distance of center of mass which is at origin of particles from 1kg mass is (approximately) (Assume 2kg on x-axis )

If the work done in stretching a wire by $1 \,mm$ is $2 J$, the work necessary for stretching another wire of same material but with double radius of cross-section and half the length by $1 \,mm$ is

If there were a smaller gravitational effect which of the following forces do you think would alter in some respect?

If the wavelength of first member of Balmer series of hydrogen spectrum is 6564 A$^\circ$, the wavelength of second member of Balmer series will be:

If the wavelength of the first line of the Balmer series of hydrogen is $6561 \, ?$, the wavelength of the second line of the series should be

If the time of flight of a projectile is doubled, what happens To the maximum height attained

If the value of force is $100 \,N$ and value of acceleration is $0.001 \,ms^{-2}\, s$, what is the value of mass in this system of units ?

If the temperature of hot black body is raised by $5\%$, rate of heat energy radiated would be increased by how much percentage ?

If the rms current in a $50\, Hz$ ac circuit is $5\, A$, the value of the current $1/300$ seconds after its value becomes zero is

If the refractive indices of crown glass for red, yellow and violet colours are 1.5140, 1.5170 and 1.5318 respectively and for flint glass these are 1.6434, 1.6499 and 1.6852 respectively, then the dispersive power for crown and flint glass are respectively:

If the radius of first Bohr's orbit is x ,then de-Broglie wavelength of electron in 3rd orbit is nearly