List of top Physics Questions

Each of the properties if sound in List-I primarily depends on one of the quantities in List-II. Select the correct answer (matching List-I with List-II) as per code given below the lists:
One of the causes of the breadth of the spectral lines is
In the circuit shown the equivalent resistance between $A$ and $B$ is
Gravitational field is
According to Bohrs theory of hydrogen atom, for the electron in the $n^{\text {th }}$ allowed orbit the (i) linear momentum is proportional to $1 / n$ (ii) radius is proportional to $n$ (iii) kinetic energy is proportional to $1 / n^2$ (iv) angular momentum is proportional to $n$ Choose the correct option from the codes given below:
The energy of an X-ray photon of wavelength $1\, ?$ is $\left( h =6.6 \times 10^{34} J - s \right)$
According to Maxwells law of distribution of velocities of molecules, the most probable velocity is
Good emitters are good absorbers is a statement concluded from
Electron volt is a unit of
In Young's double slit experiment,$1^{st}$ dark fringe occurs directly opposite a slit. Wavelength of light used is
A telescope has an objective of focal length $100\, cm$ and an eye-piece of focal length $5\, cm$. What is the magnifying power of the telescope when it is in normal adjustment ?
A sealed container with negligible coefficient of volumetric expansion contains helium (a monoatomic gas). When it is heated from 300 K to 600 K, the average KE of helium atoms is
A choke is preferred to a resistance for limiting current in AC circuit because
A convex lens of glass $(\mu=1.5)$ has a focal length of $8\, cm$ when placed in air. What is the focal length of lens when it is immersed in water $\left(\mu=\frac{4}{3}\right) ?$
An object is placed at the focus of a convex mirror. If its focal length is $20\, cm,$ the distance of mirror is
The current through a bulb is increased by $1 \%$. Assuming that the resistance of the filament remains unchanged the power of the bulb will
You are given two resistances $R_{1}$ and $R_{2} .$ By using them singly, in series and in parallel, you can obtain four resistances of $1.5\, \Omega, 2\, \Omega, 6\, \Omega$ and $8\, \Omega$. The values of $R_{1}$ and $R_{2}$ are
Two waves are represented by $y_1 = 4 \sin \, 404 \pi t$ and $y_2 = 3 \sin \, 400 \pi t.$ Then
A paramagnetic substance is placed in a weak magnetic field and its absolute temperature $T$ is increased. As a result, its magnetisation
A rectangular coil of $100$ turns and size $0.1 \times 0.05\, m$ is placed perpendicular to a magnetic field of $0.1\, T$. The induced emf when the field drops to $0.05\, T$ in $0.05\, s$ is
The equation of a simple harmonic wave is given by $y=5\, \sin \frac{\pi}{2}(100\, t-x)$, where $x$ and $y$ are in meter and time is in second. The period of the wave in second will be
A bimetallic strip consists of brass and iron when it is heated it bends into an arc with brass on the convex and iron on the concave side of the arc. This happens because
A convex lens of glass $ (\mu = 15)$ has a local length of 8 cm when placed in air. What is the strength of lens when it is immersed in water $\bigg(\mu = \frac{4}{3}\bigg) ? $
A beam of monochromatic blue light of wavelength $4200\, ?? in air travels in water of refractive index $4/3$. Its wavelength in water will be:
The twinkling effect of star light is due to