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In a plane electromagnetic wave, the directions of electric field and magnetic field are represented by [latex]hat{k}[/latex] and [latex]2hat{i}-2hat{j}[/latex], respectively. What is the unit vector along direction of propagation of the wave.

1) 2) 3) 4) Answer: (1) Unit vector along C =... View Article

A small point mass carrying some positive charge on it, is released from the edge of a table. There is a uniform electric field in this region in the horizontal direction. Which of the following options then correctly describe the trajectory of the mass? (Curves are drawn schematically and are not to scale).

Answer: (3) Since it is released from rest. And anet is constant. If will have straight line path along net ‘a’.... View Article

A wire carrying current I is bent in the shape ABCDEFA as shown, where rectangle ABCDA and ADEFA are perpendicular to each other. If the sides of the rectangles are of lengths a and b, then the magnitude and direction of magnetic moment of the loop ABCDEFA is:

1) 2) 3) 4) Answer: (3) Loop ABCD Loop DEFA Direction=... View Article

In the following digital circuit, what will be the output at ‘Z’, when the input (A,B) are (1,0), (0,0), (1,1), (0,1):

1) 0,1,0,0 2) 1,1,0,1 3) 0,0,1,0 4) 1,0,1,1 Answer: (3)... View Article

A potentiometer wire PQ of 1 m length is connected to a standard cell E₁. Another cell E₂ of emf 1.02 V is connected with a resistance ‘r’ and switch S (as shown in figure). With switch S open, the null positon is obtained at a distance of 49 cm from Q. The potential gradient in the potentiometer wire is:

1) 0.03V/cm 2) 0.02 V/cm 3) 0.04 V/cm 4) 0.01 V/cm Answer: (2) PQ= 1 m QJ = 49 cm PJ = 51 cm V/l = 1.02/51 = 0.02 v/cm... View Article

A particle is moving 5 times as fast as an electron. The ratio of the de-Broglie wavelength of the particle to that of the electron is 1.878 × 10^–4. The mass of the particle is close to:

1) 4.8 × 10–27 kg 2) 9.1 × 10–31 kg 3) 9.7 × 10–28 kg 4) 1.2 × 10–28 kg Answer: (3) = 9.7 x 10-28 Kg... View Article

Two uniform circular discs are rotating independently in the same direction around their common axis passing through their centres. The moment of inertia and angular velocity of the first disc are 0.1 kg –m² and 10 rad s^–1 respectively while those for the second one are 0.2 kg–m² and 5 rad s^–1 respectively. At some instant they get stuck together and start rotating as a single system about their common axis with some angular speed. The Kinetic energy of the combined system is:

1) 2/3 J 2) 10/3 J 3) 5/3 J 4) 20/3 J Answer: (4) Now find KE = (KE)f =(20/3)... View Article

If momentum (P), area (A) and time (T) are taken to be the fundamental quantities then the dimensional formula for energy is:

1) [P1/2 AT–1] 2) [PA1/2 T–1] 3) [PA ½ T–1] 4) [P2 AT–2] Answer: (2) =MxLx+2y Tz-x Comparing both sides :-... View Article

The number of CH2 = 0 groups present in a tripeptide Asp–Glu–Lys is ____.

Answer: 5... View Article

6.023 × 10²² molecules are present in 10 g of a substance ‘x’. The molarity of a solution containing 5 g of substance ‘x’ in 2 L solution is _____ × 10^–3.

Answer: 25 Mol. wt of ‘x’ = {10 / [6.023 × 1022]} × 6.023 × 1023 M = [5 / 100] / 2 = [(5 / 200) * 1000] × 10-3 M = 25 × 10–3 mol/lit... View Article

If 250 cm³ of an aqueous solution containing 0.73 g of a protein A is isotonic with one litre of another aqueous solution containing 1.65 g of a protein B, at 298 K, the ratio of the molecular masses of A and B is ______ × 10^–2 (to the nearest integer).

Answer: 177 [0.73 / MA] × [1000 / 250] = 1.65 / MB [MA / MB] = [73 × 4] / 165 = 1.769 = 176.9 × 10–2 = 177 × 10–2... View Article

An acidic solution of dichromate is electrolyzed for 8 minutes using 2A current. As per the following equation

Cr₂O₇^2- + 14H⁺ + 6e^– → 2Cr³⁺+ + 7H₂O

The amount of Cr³⁺ obtained was 0.104 g. The efficiency of the process (in %) is (Take: F = 96000 C, At. mass of chromium = 52) _______.

Answer: 60 % [moles of Cr3+] × 3 = [8 × 60 × 2] / 96000 Moles of Cr3+ = [8 × 4] / 9600 = (1 / 300) mol Mass of Cr3+ = (52 / 300) g %... View Article

The volume (in mL) of 0.1 N NaOH required to neutralise 10 mL of 0.1 N phosphinic acid is ___________.

Answer: 10 ml NaOH + H3 PO2 NaH2PO2 + H2O Phosphinic Volume × 0.1 = 0.1 × 10 Volume = 10 ml... View Article

Consider the following reaction:

The product 'P' gives positive ceric ammonium nitrate test. This is because of the presence of which of these –OH group(s)? 1) (b) only 2) (b)... View Article

For the reaction 2A + 3B + (3 / 2) C → 3P, which statement is correct?

1) dnA / dt = dnB / dt = dnC / dt 2) dnA / dt = (3 / 2) dnB / dt = (3 / 4) dnC / dt 3) dnA / dt = (2 / 3) dnB / dt = (4 / 3) dnC / dt 4) dnA /... View Article

Three isomers A, B and C (mol. formula C₈H₁₁N) give the following results:

Answer: (2)... View Article

A mixture of one mole each of H₂, He and O₂ each are enclosed in a cylinder of volume V at temperature T. If the partial pressure of H₂ is 2 atm, the total pressure of the gases in the cylinder is:

1) 6 atm 2) 14 atm 3) 38 atm 4) 22 atm Answer: (1) pH2 = 2 atm = xH2 × ptotal 2 atm = [(1) / (1 + 1 + 1] × ptotal ptotal = 6 atm... View Article

The compound A in the following reactions is:

Answer: (1)... View Article

The strengths of 5.6 volume hydrogen peroxide (of density 1 g/mL) in terms of mass percentage and molarity (M), respectively, are: (Take the molar mass of hydrogen peroxide as 34 g/mol)

1) 0.85 and 0.5 2) 0.85 and 0.25 3) 1.7 and 0.25 4) 1.7 and 0.5 Answer: (4) Volume strength = 5.6V Molarity = [5.6 / 11.2] = 0.5 mol / l... View Article

Consider the following molecules and statements related to them:

(a) (B) is more likely to be crystalline than (A) (b) (B) has a higher boiling point than (A) (c) (B) dissolves more readily than (A) in... View Article