List of top Physics Questions

A machine which is $75\%$ efficient, uses $12\, J$ of energy in lifting $1 \,kg$ mass through a certain distance. The mass is then allowed to fall through the same distance. The velocity at the end of its fall is
In an equilateral triangle $ABC$, $ F_{1},F_{2} $ and $ F_{3} $ are three forces acting along the sides $AB, BC$ and $AC$ as shown in the given figure. What should be the magnitude of $F_3$, so that the total torque about $ O $ is zero ?
The torque of force $\vec{ F }=(2 \hat{ i }-3 \hat{ j }+4 \hat{ k }) N$ acting at a point $\vec{ r }=(3 \hat{ i }+2 \hat{ j }+3 \hat{ k }) m$ about origin is
$300\, J$ of work is done in sliding a $2 \,kg$ block up an inclined plane of height $10 \,m$. The work done against friction is ( Take $g=10\, m / s ^{2}$ )
We wish to see inside an atom. Assuming the atom to have a diameter of $100 \,pm$, this means that one must be able to resolve a width of say $10\, pm$. If an electron microscope is used, the minimum electron energy required is about
Suppose refractive index $\mu$ is given as $\mu=A+\frac{B}{\lambda^{2}}$, where $A$ and $B$ are constants and $\lambda$ is wavelength then the dimensions of $B$ are same as that of
If a star can convert all the He nuclei completely into oxygen nuclei. The energy released per oxygen nuclei is : (Mass of the helium nucleus is 4.0026 amu and mass of oxygen nucleus is 15.9994 amu)
An infinitely long cylinder is kept parallel to an uniform magnetic field B directed along positive z-axis. The direction of induced current as seen from the 2-axis will be
In $ 1\,m $ long open pipe what is the harmonic of resonance obtained with a tuning fork of frequency $ 480\,Hz $ ?
A body of mass $ 4\,kg $ moving with velocity $ 12\,m/s $ collides with another body of mass $ 6 \,kg $ at rest. If two, bodies stick together after collision, then the loss of kinetic energy of system is
Calorie is defined as the amount of heat required to raise temperature of 1 g of water by 1$^{\circ}$C and it is defined under which of the following conditions ?
A particle moves in a circular path with decreasing speed. Choose the correct statement
Two similar coils are kept mutually perpendicular such that their centres coincide. At the centre, find the ratio of the magnetic field due to one coil and the resultant magnetic field through both coils if the same current is flown :
The potential difference between points $A$ and $B$ is:
The dimensional formula for Youngs modulus is:
A police jeep is chasing with velocity of $45\, km/h$ a thief in another jeep moving with velocity $153\,km/h$. Police fires a bullet with muzzle velocity of $180\,m/s$ The velocity it will strike the car of the thief is:
A plane glass slab is kept over various colour letters, the letter which appears least raised is:
The length, breadth and thickness of a block are given by $l=12\, cm , b=6 \,cm$ and $t=2.45 \,cm .$ The volume of the block according to the idea of significant figures should be
Five particles of mass $2\,kg$ are attached to the rim of a circular disc of radius $0.1\,m$ and negligible mass. Moment of inertia of the system about the axis passing through the centre of the disc and perpendicular to its plane is:
The radius of the convex surface of planoconvex lens is $20\,cm$ and the refractive index of the material of the lens is $1.5$. The focal length is:
A can filled with water is revolved in a vertical circle of radius $4\,m$ and the water does not fall down. What must be the maximum period of revolution?
A coil having $N$ turns carry a current as shown in the figure. The magnetic field intensity at point $P$ is:
Which mirror is to be used to obtain a parallel beam of light from a small lamp ?
If 'muscle times speed equals power' what is the ratio of the $SI$ unit and the $CGS$ unit of muscle?
An object travels north with a velocity of $ 10\,m{{s}^{-1}} $ and then speeds up to a velocity of $ 25\,m{{s}^{-1}} $ in 5 s. The acceleration of the object in these 5 s is: