List of top Physics Questions

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 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 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 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
A parallel monochromatic beam of light is incident normally on a narrow slit. A diffraction pattern is formed on a screen placed perpendicular to the direction of the incident beam. At the first minimum of the diffraction pattern, the phase difference between the rays coming from the two edges of slit is
A ray of light passes through an equilateral prism such that the angle of incidence is equal to the angle of emergence and the latter is equal to $ \frac{3}{4} $ the angle of prism. The angle of deviation is
The critical angle for total internal reflection in diamond is $ 24.5^{\circ} $ . The refractive index of the diamond is
For what distance is ray optics a good approximation when the aperture is $4 \,mm$ wide and the wavelength is $500 \,nm$?
For what distance is ray optics a good approximation when the aperture is $4 \,mm$ wide and the wavelength is $500 \,nm$?
Number of neutrons in $C^{12}$ and $ C^{14} \, are $
Sharp peak point $A$ represents
The temperature of a body is increased from $-73^{\circ}\,C$ to $327\,^{\circ}\,C$. Then the ratio of emissive power is
Which shows radioactivity?