List of top Physics Questions

A body has a charge of -3.2μC . The number of excess electrons it has is

The angular velocity of earth's rotation about its axis is $'\omega'.$ An object weighed by a spring balance gives the same reading at the eiquator as at a height 'h' above the poles. The value o f 'h' will be

An electric blub of 60 W, 120 V is to be connected to 220 V source. What resistance should be connected in series with the bulb, so that the bulb glows properly?

A particle moves in xy plane according to the law x = a sin ωt and y = a(1 - cos ωt), where a and w are constant. The particle traces

Light incident normally on a plane mirror attached to a galvanometer coil retraces backwards as shown in Fig. 9.29. A current in the coil produces a deflection of 3.5o of the mirror. What is the displacement of the reflected spot of light on a screen placed 1.5 m away?

Current flows through uniform, square frames as shown in the figure. In which case is the magnetic field at the centre of the frame not zero?

Among two discs $A$ and $B$, first has radius $10 \,cm$ and charge $ 10^{-6} \mu C$ and second has radius $30 \,cm$ and charge $10^{-5}C$ . When they are touched, charges on both are, $q_{A}$ and $q_{B}$ respectively, will be

The graphs shows, angular velocity as a function of time. In which one is the magnitude of the angular acceleration constantly decreasing?

The ratio of the respective de Broglie wavelengths associated with electrons accelerated from rest with the voltages 100 V, 200 V and 300 V is

A body of mass 5 kg is initially at rest on a smooth horizontal surface. A constant force of 20 N is applied to the body. Find the acceleration of the body and the distance traveled by the body in 10 seconds.

A cube of side 1 cm contains 100 molecules each having an induced dipole moment of 0.2×10^-6C-m in an external electric field of 4NC^-1. The electric susceptibility of the materials is_____ C2N^-1m^-2

A cell of constant emf first connected to a resistance $ {{R}_{1}} $ and then connected to a resistance $ {{R}_{2}} $ . If power delivered in both cases is same, then the internal resistance of the cell is

An electron moves in a circle of radius $1.0 \,cm$ with a constant speed of $ 4.0\times {{10}^{6}}m/s $ , the electric current at a point on the circle will be $ (e=1.6\times {{10}^{-19}}C) $

How does the dynamic resistance of diode vary with temperature?

To get a resultant displacement of 10 m two displacement vectors, one of magnitude 6m and another of 8m should be combined.

The output Y for the inputs A and B of circuit is given by Truth table of the shown circuit is:

A body is projected vertically upwards with a velocity u. It crosses a point in its journey at a height h twice, just after 1 and 7 s. The value of $ \mu $ is ms-1 is: $ (g=10{{m}^{-2}}) $

A bullet when fired into a target loses half of its velocity after penetrating $20\, cm$. Further distance of penetration before it comes to rest is

Let $\sigma$ be the uniform surface charge density of two infinite thin plane sheets shown in figure Then the electric fields in three different region $E_I, E_{I I}$ and $E_{I I I}$ are:

A wave

y = a \sin (ω t - k x)

on a string meets with another wave producing a node at

x = 0

. Then the equation of the unknown wave is:

Two particles

A

and

B

of equal masses are suspended from two massless springs of spring constants

k_{1}

and

k_{2}

respectively. If the maximum velocities, during oscillations, are equal, the ratio of amplitudes of

A

and

B

is:

A short linear object of length b lies along the axis of a concave mirror of focal length

f

at a distance

u

from the pole of the mirror. The size of the image is approximately equal to:

At a hydroelectric power plant, the water pressure head is at a height of

300 m

and the water flow available is

100 m^{3} s^{- 1}

. If the turbine generator efficiency is

60 %

, estimate the electric power available from the plant.

(

Given

g = 9.8 {m s}^{- 2})

In a parallel plate capacitor with air between the plates, each plate has an area of 6 × 10^–3 m² and the distance between the plates is 3 mm. Calculate the capacitance of the capacitor. If this capacitor is connected to a 100 V supply, what is the charge on each plate of the capacitor?

If the angle of minimum deviation is equal to angle of a prism for an equilateral prism, then the speed of light inside the prism is _____