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Compound ‘X’ will be

Answer: (b)... View Article

Write IUPAC name of the following compound

a. 3-Hydroxy-2-methylpentanoic acid b. 4-Methyl-3-hydroxypentanoic acid c. 3-Hydroxy-4-methylpentanoic acid d. 2-Methyl-2-hydroxypentanoic... View Article

The correct order of K_b value of the following is

a. 1 > 2 > 3 b. 1 > 3 > 2 c. 3 > 2 > 1 d. 3 > 1 > 2 Answer: (b) kb ∝ Basic strength. Basic strength ∝... View Article

Reaction of dilute HCl with Maltose gives:

a. D – glucose b. D – fructose c. D – glucose and D – fructose d. D – galactose Answer: (a) Maltose is a dissacalaride, consisting of 2... View Article

Which of the following amine will be prepared by Gabriel phthalimide reaction?

a. n-Butylamine b. Triethylamine c. neo-Pentylamine d. tert-Butylamine Answer: (a) Gabriel pthalimide synthesis is used to prepare 10... View Article

A prism is shown in the figure with prism angle 75° and refractive index √3. A light ray incidents on a surface at incident angle θ. Other face is coated with a medium of refractive index n. For θ ≤ 60⁰ ray suffers total internal reflection find value of n².

Answer: 1.5... View Article

In a given circuit inductor of L = 1mH and resistance R = 1Ω are connected in series to ends of two parallel conducting rods as shown. Now a rod of length 10 cm is moved with constant velocity of 1 cm/s in magnetic field B = 1T. If rod starts moving at t = 0 then current in circuit after 1 millisecond is x . 10^-3 A. Then value of x is: (given e^-1 = 0.37)

Answer: 0.63 mA e = (V x B) dl = 10-3 v df i = 10-3(1 – e-1) i = 0.63 mA... View Article

Calculate the work done if a particle is moved along a path AB−BC−CD−DE−EF−FA, as shown in the figure in presence of a force [latex]vec{F} = (alpha yhat{ii} + 2alpha xhat{j})N[/latex], where x and y are in meter and [latex]alpha w = -1Nm^{-1}[/latex].

Answer: 0.75 J dω = αy dx + 2αx dx E → F, y = 0, dy = 0, WEF = 0 F → A, x = 0, dx = 0, WF → A = 0 ∴ w = α − α − α / 4 − α / 2 =... View Article

In a cylinder a heavy piston is moving with speed v as shown diagram and gas is filled inside it. A gas molecule is moving with speed v₀ towards moving piston. Then which of the following is correct. (Assume v <<<< v₀ Δl/l ) and collision is elastic)

a) change in speed after collision is 2V b) change is speed after collision is 2 v0 Δl/l c) rate of collision is V/l d) When piston is at... View Article

A free hydrogen atom after absorbing a photon of wavelength λ_a gets excited from state n = 1 to n = 4. Immediately after electron jumps to n = m state by emitting a photon of wavelength λ_e. Let change in momentum of atom due to the absorption and the emission are ΔP_a and Δp_e respectively. If λ_a/ λ_e= 1/5. Which of the following is correct

a) m = 2 b) ΔPa/Pe = 1/2 c) λe = 418 nm d) Ratio of K.E. of electron in the state n = m to n = 1 is ¼. Answer: a::d... View Article

A dipole of Dipole moment [latex]p = frac{p_0}{sqrt 2}(hat i + hat j)[/latex] is placed at origin. Now a uniform external electric field at magnitude E₀ is applied along direction of dipole. Two points A and B are lying on a equipotential surface of radius R centered at origin. A is along axial position of dipole and B is along equatorial position. There correct option are:

a) Net electric field at point A is 3E0 b) Net electric field at point B is Zero c) Radius of equatorial surface R = (kp0/E0)1/3 d) Radius... View Article

The given arrangement is released from rest when spring is in natural length. Maximum extension in spring during the motion is x₀, a₁, a₂ and a₃ are accelerations of the blocks.

Make the correct options a) a2 – a1 = a1 – a3 b) x0 = 4mg/3k c) d) Acceleration a1 at x0/4 is 3kx0/42m Answer: a::c::d 2a1 = a2 +... View Article

Monoatomic gas A having 5 mole is mixed with diatomic gas B having 1 mole in container of volume V0. Now the volume of mixture is compressed to V0/4 by adiabatic process. Initial pressure and temperature of gas mixture is P₀ and T₀. [given 2^3.2 = 9.2] Choose correct option:

a) b) Final pressure is between 9P0 and 10P0 c) |W.D.| = 13 RT0 d) Average Translational kinetic energy Answer: a::b::c W = [P1V1 –... View Article

A uniform rigid rod of mass m & length l is released from vertical position on rough surface with sufficient friction for lower end not to slip as shown in figure. When rod makes angle 60° with vertical then find correct alternatives

a) b) c) N = mg/16 d) aradical = 3g/4 Answer: b::c::d mg – N = mav N = mg/16... View Article

In YDSE monochromatic light of wavelength 600 nm incident of slits as shown in figure.

If S1S2 = 3mm, OP = 11 mm then a) If α = 0.36/π degree then destructive interfaces at point P. b) If α = 0.36/π degree then constructive... View Article

Consider two plane convex lens of same radius of curvature and refractive index n₁ and n₂ respectively. Now consider two cases:

Case – I: When n1 = n2 = n, then equivalent focal length of lens is f0. Case – II: When n1 = n, n2 = n + Δn, then equivalent focal length of... View Article

An optical bench, to measure the focal length of lens, is 1.5 m long and on the bench marks are with spacing 1/4 cm. Now a lens is placed at 75 cm and pin type object is placed at 45 cm marks on the bench. If its image is formed at 135 cm find maximum possible error in calculation of focal length.

Answer: df/f = 1.38 and 1.39 V = 30 cm and dv = 0.5 cm V = 60 cm and dv = 0.5 cm Now, using lens formula, 1/v - 1/u = 1/f 1/60 + 1/30 = 1/f... View Article

A weight of 100 N is suspended by two wires made by steel and copper as shown in figure length of steel wire is 1 m and copper wire is √3 m. Find ratio of change in length of copper wire (Δ l₀) to change in length of steel wire (Δ l_s). Given Young’s modulus: Y_steel= 2 × 10¹¹ N/m², Y_copper = 1 × 10¹¹ N/m².

Answer: 2... View Article

The source S₁ is at rest. The observer and the source S₂ are moving towards S₁ as shown in figure. The roof beats observed by the observer if both sources have frequency 120 Hz and speed of sound 330 m/s in is

Answer: 8.128Hz... View Article

If at angle θ the light takes maximum time to travel in optical fiber. Then the maximum time is x (10^-8), calculate x.

Answer: 10 1.5 sin θC = 1.44 sin 900 sin θC = 24/25 and sin θC = x/d ⇒ d = 25x/24 Now, t = L/(C/n2) = 5 x 10-8s Putting: C = 3... View Article