List of top Physics Questions

A man in a car at location $Q$ on a straight highway is moving with speed $v$. He decides to reach a point $P$ in a field at a distance d from the highway (point $M$) as shown in the figure. Speed of the car in the field is half to that on the highway. What should be the distance $RM$, so that the time taken to reach $P$ is minimum ?

A gill throws a stone horizontally from the roof of a house 12 in above the ground with a speed of If 15 m/s. Neglecting air resistance, the time it takes tor the stone to reach the ground is

Consider a 50 in high water falls, with water flowing at a rate of $1.2 \times 10^6 \, kg/s$. Using the power generated due to this process, assuming 100% efficiency, the number of 60W bulbs that can be light up is

In analysing the problems of inelastic collisions, the law of conservation of momentum and the law of conservation of mechanical energy are to be employed Since the laws of conservation of momentum and mechanical energy are fundamental laws, they should hold good in any situation. Which of the following is true?

A rocket is about to launch upwards from its platform. The engine ejects gas at a rate of 2100 kg/s and the molecules are expelled at 50 m/s. If the above condition is just sufficient to make it rise upwards, the mass of the rocket is (Assume $g = 10\, ms^2$)

Elastic strain energy of 10 J is stored in a loaded copper rod of cross-sectional area $2 times 10^{-4} m^2$ and length 0,2 in, Hie Young?? modulus for copper is 125 GPa. The load on the copper rod in kN is

The CGS unit of coefficient of viscosity is

Consider a ship traveling due east along the equator with velocity $v_0$. If southeastern wind blows at an angle of $' \phi '$ to the equator with velocity $'v'$, the wind velocity relative to the ship $v'$ and the angle between the equator and the wind direction in the reference frame fixed to the ship are

A cannon ball is fired from a building of height h at the sea shore with a velocity v at an angle of a upwards from the horizontal, targeting a ship at a horizontal distance of S from the shore, as shown in the figure. If 'g' denotes the acceleration due to gravity, tan $\alpha$ governed by the quadratic equation is

Which of the set has different dimensional formulae :

Hie equation of motion of a panicle is given by $x(t) = 2t^3 + t^2 + 4t$. Then the average velocity of the particle between the time t = 3 s to t = 5 s is

An electron moves in a combined electric and magnetic field, the electric field being $1.5 \times 10^3 \, V/m$ and magnetic field being 0.75 T. If the resultant force on the moving electron is to be zero, the minimum velocity of the electron in km s is

A body is projected with a speed 'u? at an angle $'\theta'$ with the horizontal. The radius of curvature of the trajectory when it makes an angle $\left(\frac{\theta}{2} \right)$ with the horizontal is (g - acceleration due to gravity)

Two particle are moving in opposite direction with speed v₁ and v₂. What may be their velocity if relative velocity is 6 m/sec

The half-life of tritium is 12.5 years. What mass of tritium of initial mass 64 mg will remain undecayed after 50 years ?

If a machine perform 4000 J output work and 1000 J is inside loss due to friction, then find the efficiency?

A plane polarized monochromatic $EM $ wave is traveling in vacuum along $z$ direction such that at $t = t_1$ it is found that the electric field is zero at a spatial point $z_1$. The next zero that occurs in its neighbourhood is at $z_2$. The frequency of the electromagnetic wave is :

Find i = ?

A silver atom in a solid oscillates in simple harmonic motion in some direction with a frequency of $10^{12} / \sec$. What is the force constant of the bonds connecting one atom with the other ? ( Mole wt. of silver $= 108 $ and Avogadro number $= 6.02 \times 10^{23} \, gm \, mole^{-1} $ )

The maximum efficiency of a half wave rectifier is

The transition in He⁺ ion that will give rise to a spectral line having the same wavelength as that of some spectral line in hydrogen atom is______

A feedback circuit usually employs ..... network

In an amplifier with negative feedback, the bandwidth is

In the JJ Thomson method for the determination of e/m what is the angle between the magnetic & electric fields to which the electrons are subjected?