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National Green Highways Mission (NGHM)

The Government of India is implementing many schemes and programs in order to mitigate the impacts of pollution and climate change. A program in... View Article

Himalayan Serow

Himalayan Serow - a Himalayan mammal, somewhere between a goat and an antelope, has been confirmed as the newest creature to be spotted in... View Article

National Civil Services Day

Every Year, National Civil Services Day is celebrated on April 21st by the Government of India. The Civil Services Day is dedicated to India's... View Article

23 July 2021: The Hindu Analysis

UPSC Current Affairs Preparation: The Hindu Analysis Watch expert analysis of ‘The Hindu’ dated 23rd Jul 2021. Important news and views to boost... View Article

National Panchayati Raj Day – NPRD

National Panchayati Raj Day is recognized on April 24th every year by the Ministry of Panchayati Raj. The information on Panchayati Raj Day... View Article

Indian Council for Agricultural Research [ICAR]

Indian Council for Agricultural Research, full-form of ICAR, is the largest network of agricultural research and education institutes in the... View Article

Gandhian Ideology

Gandhian ideology (also known as Gandhism) is the set of religious and social ideas adopted and developed by India’s Father of Nation, Mahatma... View Article

In a collinear collision, a particle with an initial speed v₀ strikes a stationary particle of the same mass. If the final total kinetic energy is 50% greater than the original kinetic energy, the magnitude of the relative velocity between the two particles, after collision, is:

a. V0/2 b. V0/√2 c. V0/4 d. √2 V0 Answer: (d) L.M.C mv1+mv2= mv0 V1+V2=V0----------(I) Initial KE = (1/2)mV02 Final KE = (1/2)mV12... View Article

From a uniform circular disc of radius R and mass 9 M, a small disc of radius R/3 is removed as shown in the figure. The moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through centre of disc is:

a. 10 MR2 b. (37/9) MR2 c. 4 MR2 d. (40/9)MR2 Answer: (c)... View Article

A silver atom in a solid oscillates in simple harmonic motion in some direction with a frequency of 10¹²/sec. What is the force constant of the bonds connecting one atom with the other? (Mole wt. of silver = 108 and Avagadro number = 6.02 x 10²³ gm mole^-1

a. 2.2 N/m b. 5.5 N/m c. 6.4 N/m d. 7.1 N/m Answer: (d) Frequency K =m(2 πf))2 Mass of 1 atom m=18 x 10-26 Kg k = 18 x 10-26(2π... View Article

The angular width of the central maximum in a single slit diffraction pattern is 60⁰. The width ofthe slit is 1μm. The slit is illuminated by monochromatic plane waves. If another slit of same width is made near it, Young’s fringes can be observed on a screen placed at a distance 50 cm from the slits. If the observed fringe width is 1 cm, what is slit separation distance? (i.e., distance between the cenrtres of each slit.)

a. 75 μm b. 100 μm c. 25 μm d. 50 μm Answer: (c) 2α = 600 a=1 μm D = 50 cm (Cond. for minima/Path diff Δx = a sin θ = n λ)... View Article

Three concentric metal shells A, B and C of respective radii a, b and c (a < b < c) have surface charge densities + σ, -σ and +σ respectively. The potential of shell B is:

a. b. c. d. Answer: (d)... View Article

Seven identical circular planar disks, each of mass M and radius R are welded symmetrically as shown. The moment of inertia of the arrangement about the axis normal to the plane and passing through the point P is:

a. b. c. d. Answer: (b) M.I. about origin... View Article

A granite rod of 60 cm length is clamed at its middle point and is set into longitudinal vibrations. The density of granite is 2.7 x 10³ kg/m³ and its Young’s modulus is 9.27 x 10¹⁰ Pa. What will be the fundamental frequency of the longitudinal vibrations?

a. 10 kHz b. 7.5 kHz c. 5kHz d. 2.5 kHz Answer: (c) On substituting the value, we get the required answer.... View Article

A telephonic communication service is working at carrier frequency of 10 GHz. Only 10% of it is utilized for transmission. How?

a. 2 x 105 b. 2 x 105 c. 2 x 103 d. 2 x 104 Answer: (a) No of channels =(carrier frequencyx0.1)/channel bandwidth = (0.1 x 10 x 109)/(5 x 103)=... View Article

For an RLC circuit driven with voltage of amplitude V_m and frequency [latex]omega _{0}=frac{1}{sqrt{LC}}[/latex] the current exhibits resonance. The quality factor, Q is given by:

a. b. c. d. Answer: (c) Quantity factor -------from theory... View Article

a parallel plate capacitor of capacitance 90 pf is connected to a battery of emf 20v if a dielectric material of dielectric constant k equal 5 by 3 is inserted between the plates the magnitude of the induced charge will be

a. 2.4 nC b. 0.9 nC c. 1.2 nC d. 0.3 nC Solution: Option (c) 1.2 nC Explanation: Battery remains connected as dielectric is introduced So... View Article

An electron, a proton and an alpha particle having the same kinetic energy are moving in circular orbits of radii r_e, r_p, r_α respectively in a uniform magnetic field B. The relation between r_e, r_p, r_α is:

a. re < rp < rα b. re < rα < rp c. re > rp = rα d. re < rp = rα Answer: (d) r = mv/qB = p/qB K... View Article

The reading of the ammeter for a silicon diode in the given circuit is:

a. 11.5 mA b. 13.5 mA c. 0 d. 15 mA Answer: (a) Knowledge based Si diode has forward bias resistance 200 at 2 V 400 at 1 V ⇒ here Rfb <... View Article

An electron from various excited states of hydrogen atom emit radiation to come to the ground state. Let λ_n, λ_g be the de Broglie wavelength of the electron in the n^th state and the ground state respectively. Let A_n be the wavelength of the emitted photon in the transition from the n^th state to the ground state. For large n, (A, B are constants)

a. Λ2n≈ A+B λ2n b. Λ2n≈ λ c. Λn≈A + (B/ λ2n) d. Λn≈A + Bλn Answer: (c) mvr = (nh/2 π) λde Broglie = (h/p) = (2 πr/n) λn =(2 πrn/n)... View Article