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Water softening by Clark’s process uses:

(A) Potash Alum (B) Calcium hydroxide (C) Sodium bicarbonate (D) Calcium bicarbonate The Correct Answer is (B) Solution: Calcium... View Article

Which of the following statement is true about the Lattice?

(A) It is a regular repeated three-dimensional arrangement of atoms (B) It is a series of points that are arranged in a distinct pattern. (C)... View Article

Which has the maximum number of molecules?

(A) 2gH2 (B) 7gN2 (C) 16gO2 (D) 16gNO2 The Correct Answer is (A) 2gH2 Solution: (A) 2gH2 The number of moles in 2gH2 Molar mass of H2 = 2... View Article

Which of the following is diamagnetism?

(A) Quartz (B) Nickel (C) Bismuth (D) Aluminium The Correct Answer is (C) Bismuth Solution: Bismuth is a naturally diamagnetic compound.... View Article

The value of [latex](z+3)(bar{z}+3)[/latex] is equivalent to

Solution: Let z = x+iy Then = (x+iy+3)(x-iy+3) = (x+3+iy)(x+3-iy) = (x+3)2 - (iy)2 = (x+3)2 + y2 = |x+3+iy|2 = |z+3|2 Hence... View Article

Find prime factorisation of 5929

Solution: 5929 prime factorisation steps are given below. The first step is to divide the number 5929 with the smallest prime factor, here it... View Article

Let f(x) be a non-negative continuous function such that the area bounded by the curve y = f(x), x-axis and the ordinates x = π/4 and x = β > π/4 is (β sin β + (π/4) cos β + √2β). Then f(π/2) is

Solution: Given ∫π/4β f(x) dx = (β sin β + (π/4) cos β + √2β Differentiate both sides w.r.t.β... View Article

The angle bisector of a triangle divides the opposite side into two parts proportional to the other two sides of the triangle. Prove it.

Solution: Let ABC be the triangle. AD is the internal bisector of ∠BAC which meets BC at D. We have to prove BD/DC = AB/AC Draw CE parallel... View Article

How to convert an improper fraction into a mixed fraction?

Solution: To convert an improper fraction to a mixed fraction, we should divide the numerator by the denominator. Then write down the quotient... View Article

What is central angle?

Solution: A central angle is an angle whose vertex is the centre of a circle and whose arms are radii intersecting the circle at two distinct... View Article

How to calculate quartiles?

Solution: We can calculate the quartiles using the formulas given below. First quartile, Q1 = (n + 1)/4th term Second quartile, Q2 =... View Article

How to calculate coefficient of correlation?

Solution: We can calculate Pearson’s coefficient of correlation using the following formula. ρ(X,Y) = cov (X,Y) /... View Article

A ball is projected horizontally. After 3 second from projection its velocity becomes 1.25 times of the velocity of projection. Its velocity of projection is:-

a) 10 m/s b) 20 m/s c) 30 m/s d) 40 m/s Answer: d) 40 m/s Solution: vy = uy + ayt vy = 0 + 9.8 x 3 = 29. 4 m/s v'... View Article

The shape of drops and bubbles are spherical due to its

a) thrust on drop b) surface tension c) viscosity d) residual pressure Answer: b) surface tension Solution: A liquid surface... View Article

The solenoid has a core with a material of relative permeability of 500. The windings of the solenoid are insulated from the core and carry a current of 1A. If the number of turns is 500 per meter, then magnetisation is?

a) 2.5 x 103 A/m b) 2.5 x 105 A/m c) 2.0 x 103 A/m d) 2.0 x 103 A/m Answer: b) 2.5 x 105 A/m Solution: Here, n = 500... View Article

Explain surface tension on the basis of the molecular theory.

All the molecules in the liquid are pulled by other water molecules due to intermolecular force. The forces on a molecule are balanced out by... View Article

In the circuit shown here, the point ‘C’ is kept connected to point ‘A’ till the current flowing through the circuit becomes constant. Afterward, suddenly, point ‘C’ is disconnected from point ‘A’ and connected to point ‘B’ at time t=0. Ratio of the voltage across resistance and the inductor at t =L/R will be equal to:

a) 0 b) 1 c) -1 d) infinity Answer: c) -1 Solution:' Let the emf of the battery be E.From the question, the point C of the circuit is... View Article

A 4 cm tall object is placed perpendicular to the principal axis of a convex lens of focal length 24 cm. The distance of the object from the lens is 16 cm. Find the position, size and nature of the image formed, using the lens formula.

Solution: For convex lens f=+24cm,u=−16cm Using lens formula (1/f)=(1/v)−(1/u) (1/24)=(1/v)−(1/−16)... View Article

A block of weight W is suspended by a string of fixed length. The ends of the string are held at various positions as shown in the figures below. In which case, if any, is the magnitude of the tension along the string largest?

a. b. c. d. Answer: a Solution: From the free body diagrams 2Tcosθ = W Hence, T = W/2cosθ. If the θ increases then cosθ will decrease... View Article

A train is moving due east and a car is moving due north with equal speeds. A passenger in the train finds that the car is moving towards

a) North - East b) North - West c) South - West d) South - East Answer: b) North - West Solution: Let be the velocity of the train. We... View Article

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