List of top Physics Questions

A particle has initial velocity \( 2\hat{i} + 3\hat{j} \) \( ms^{-1} \) and acceleration \( 0.8\hat{i} + 0.6\hat{j} \) \( ms^{-2} \). Its velocity after 5 sec is (in \( ms^{-1} \)):

A box of mass 15 kg is kept on the floor of a stationary trolley. The coefficient of static friction between the box and the trolley is 0.12. Keeping the box in stationary state over the trolley, the maximum acceleration with which the trolley can be moved horizontally in m s⁻² is: ____.

A particle moves with uniform speed along a circular path. The direction of its acceleration (if any) is-

A particle moves uniformly in a circular path of radius 10 m. It takes 10 s to complete one revolution. Its speed after 20 s will be-

The relative density of silver is 10.8. If the density of water is 1000 kg/m\(^3\), then the density of silver will be-

A boy of mass 50 kg runs with a speed of 4 m/s. His kinetic energy is-

Which type of radiation consists of high-energy photons with no mass or charge?

During short circuiting, the electric current in the circuit-

A 2 kW air conditioner works for 8 hours per day. At the rate of Rs 6/kWh the electricity bill for one day will be-

The value of the universal gravitational constant \(G=6.67\times10^{-11}\,Nm^{2}/kg^{2}\) in CGS system is-

A 100-turn closely wound circular coil of radius 5 cm has a magnetic field of 3.14 $\times$ 10⁻³ T at its centre. The current flowing through the coil, and the magnitude of the magnetic moment of this coil are, respectively: (Take $\mu_0 = 4\pi \times 10^{-7}$ T m/A)

Magnetic flux of a $20$ turn coil is reduced to zero from $0.3\,Wb$ in one second. The induced e.m.f. between the terminals of the coil is

In a superconducting ring, a persistent current has been flowing without decay for years. This is possible because:

In Optical Fiber communication, the signal is transmitted in the form of:

In a photoelectric experiment, the stopping potential for incident light of wavelength 4000 Å is 2 V. If the wavelength is changed to 3000 Å, the new stopping potential will be approximately:

The R.M.S. speed of oxygen molecules at 27 °C is $v$. At 927 °C the rms speed will be:

A bubble of an ideal gas rises from the bottom of a lake to the surface. At the bottom, the pressure is 3 Atm. and the temperature is 7 °C. At the surface, the pressure is 1 atm. and the temperature is 27 °C. If the initial volume of the bubble was $V_0$ what is its volume $V_f$ at the surface?

At constant temperature, the product PV is plotted against pressure P for an ideal gas. The graph obtained is:

If the pressure of an ideal gas is doubled and its absolute temperature is halved; the volume will become:

In an Isothermal process:

In a closed hall of volume 5000 m³, the total absorption of the interior surfaces is 200 metric sabin. The reverberation time is:

If the volume of a room is doubled and the total absorption is halved, the reverberation time will:

In Acoustics, 'Noise' is generally characterized by:

A source of sound of frequency 500Hz is moving towards an observer with velocity $30m/s$. The speed of sound is $330m/s$. The frequency heard by the observer will be:

Two identical piano wires, when tuned to a fundamental frequency of 400 Hz, produce no beats. One wire is then slightly tightened, and the beat frequency heard is 2 Hz. What is the new fundamental frequency of the tightened wire?