List of top Physics Questions

The diagrams below show regions of equipotentials.

A positive charge is moved from A to B in each diagram.

Thermodynamic processes are indicated in the following diagram.

Match the following

Column-1		Column-2
P.	Process I	a.	Adiabatic
Q.	Process II	b.	Isobaric
R.	Process III	c.	Isochoric
S.	Process IV	d.	Isothermal

Suppose the charge of a proton and an electron differ slightly. One of them is –e, the other is (e +△e). If the net of electrostatic force and gravitational force between two hydrogen atoms placed at a distance d (much greater than atomic size) apart is zero, then △e is of the order of [Given mass of hydrogen m_h = 1.67 × 10^–27 kg]

Two rods A and B of different materials are welded together as shown in figure. Their thermal conductivities are K₁ and K₂. The thermal conductivity of the composite rod will be

A particle executes linear simple harmonic motion with an amplitude of 3 cm. When the particle is at 2 cm from the mean position, the magnitude of its velocity is equal to that of its acceleration. Then its time period in seconds is

Figure shows a circuit contains three identical resistors with resistance R=9.0 Ω each,two identical inductors with inductance L=2.0 mH each, and an ideal battery with emf ε=18 V. The current 'i' through the battery just after the switch closed is

The de-Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (Kelvin) and mass m, is

A U tube with both ends open to the atmosphere, is partially filled with water. Oil, which is immiscible with water, is poured into one side until it stands at a distance of 10 mm above the water level on the other side. Meanwhile the water rises by 65 mm from its original level (see diagram). The density of the oil is

The x and y coordinates of the particle at any time are x = 5t – 2t² and y = 10t respectively, where x and y are in meters and t in seconds. The acceleration of the particle at t = 2 s is

A 250-Turn rectangular coil of length 2.1 cm and width 1.25 cm carries a current of 85 μA and subjected to a magnetic field of strength 0.85 T. Work done for rotating the coil by 180° against the torque is

One end of string of length l is connected to a particle of mass ‘m’ and the other end is connected to a small peg on a smooth horizontal table. If the particle moves in circle with speed ‘v’, the net force on the particle (directed towards center) will be (T represents the tension in the string)

Radioactive material 'A' has decay constant '8λ' and material 'B' has decay constant 'λ'. Initially they have same number of nuclei. After what time, the ratio of number of nuclei of material 'B' to that 'A' will be \(\frac 1e\) ?

A potentiometer is an accurate and versatile device to make electrical measurements of E.M.F, because the method involves :

A gas mixture consists of 2 moles of O₂ and 4 moles of Ar at temperature T. Neglecting all vibrational modes, the total internal energy of the system is

A physical quantity of the dimensions of length that can be formed out of c, G and $\frac{e^2}{4 \pi \varepsilon_0} $ is [c is velocity of light, G is universal constant of gravitation and e is charge] :-

A carnot engine having an efficiency of $\frac{1}{10} $ as heat engine, is used as a refrigerator. If the work done on the system is $10\,J$, the amount of energy absorbed from the reservoir at lower temperature is :

A resistance of $ 5 \Omega $ is connected in series with a capacitance of $ 1\,mF $ . The combination is connected to $ AC $ source of angular frequency $ 200 \, rad\, s ^{-1} $ . Then

A body $ A $ thrown vertical upwards with a velocity v reaches a height of $ 200\, m $ . Another body $ B $ whose mass is twice that of $ A $ is thrown with a velocity $ 2v $ . Find the maximum height reached by $ B $ .

A particle performs linear $S.H.M.$ At a particular instant, velocity of the particle is $u$ and acceleration is $\alpha$ while at another instant velocity is $v$ and acceleration is $ \beta (0 < \alpha < \beta )$. The distance between the two positions is

Two spherical black bodies have radii $?r_1?$ and $'r_2'$ . Their surface temperatures are $'T_1'$ and $'T_2'$. If they radiate same power then $\frac{r_2}{r_1}$ is

A disc of moment of inertia $'I_1'$ is rotating in horizontal plane about an axis passing through a centre and perpendicular to its plane w ith constant angular speed $?\omega_1'$. Another disc of moment of inertia $?I_2? $ having zero angular speed is placed coaxially on a rotating disc. Now both the. discs are rotating with constant angular speed $?\Omega_2 ?$. The energy lost by the initial rotating disc is

A solid sphere of mass 2 kg is rolling on a frictionless horizontal surface with velocity 6 m/s. It collides on the free end of an ideal spring whose other end is fixed. The maximum compression produced in the spring will be (Force constant of the spring = 36 N/m).

If $\theta_1$ and $\theta_2$ be the apparent angles of dip observed in two vertical planes at right angles to each other, then the true angle of dip $\theta$ is given by :

A particle executes linear simple harmonic motion with an amplitude of $3 \,cm$. When the particle is at $2\,cm$ from the mean position, the magnitude of its velocity is equal to that of its acceleration. Then its time period in seconds is :