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If U={1,2,3,4,5,6,7,8,9}, A={2,4,6,8} and B={2,3,5,7}. Verify that (i) (A∪B)′ =A ′∩B′ (ii) (A∩B)′ = A′∪B′

Given, U={1,2,3,4,5,6,7,8,9}, A={2,4,6,8} and B={2,3,5,7} We need to verify: (i) (A∪B)′ =A ′∩B′ A∪B =... View Article

Who is the first indian woman to climb the Mt.Everest?

Bachendri Pal, in 1984, became the first Indian woman to reach the summit of Mount Everest.... View Article

Parenchyma cells are (a)Relatively unspecified and thin-walled (b)Thick-walled and specialized (c)Lignified (d)None of these

Answer: (a)Relatively unspecified and thin-walled Parenchyma is a type of simple permanent tissue that makes a major part of ground tissues in... View Article

Find the sum and product of the roots of the quadratic equation:x^2 – 5x + 8 = 0.

If ax2 +bx+c is a quadratic equation, then; sum of roots = -b/a product of roots = c/a Given, x2 - 5x + 8 = 0 is a quadratic equation. Sum of... View Article

Name the scientists who have contributed to the following. (i) Reverse transcription. (ii) Photorespiration. (iii) Principle of limiting factors. (iv) Photolysis of water.

(i) Reverse transcription - Howard Temin and David Baltimore (ii) Photorespiration - Decker and Tio (iii) Principle of limiting... View Article

Main axis of diatomic molecule is z, molecular orbital px and py overlap to form which of the following orbitals. (a) π molecular orbital (b) σ molecular orbital (c) δ molecular orbital (d) No bond will form

Answer: (a) π molecular orbital... View Article

An electric kettle has two heating coils. When one of the coils is connected to an A.C source, the water in the kettle boils in 10 minutes. When the other coil is used the water boils in 40 minutes. If both the coils are connected in parallel, the time taken by the same quantity of water to boil will be: (A) 8 min (B) 4 min (C) 25 min (D) 15 min

Let us suppose, resistance of the two coils be R1 and R2 Voltage supplied = V Effective resistance of two coils in parallel = (R1.R2) /(R1+R2)... View Article

Two equal drops of water are falling through air with steady velocity v. If the drops coalesced, what will be the new velocity ?

As per the given question. vt ∝ r2 4/3 π R3 = 2 x 4/3 π r3 R = 21/3 r >v2/v1 = (r2/r1)2 = (R/r)2 = 22/3... View Article

State the Kohlrausch law of independent migration of ions. Why does the conductivity of a solution decrease with dilution?

Kohlrausch’s law states that the equivalent conductivity of an electrolyte at infinite dilution is equal to the sum of the conductances of... View Article

Name two quantities which remain conserved during nuclear reaction.

The quantities, which remain conserved In a nuclear reaction: Total Charge Angular momentum Linear momentum... View Article

Thermodynamics is not concerned about_____ A.The energy changes involved in a chemical reaction. B.The extent to which a chemical reaction proceeds. C.The rate at which the reaction proceeds. D.The feasibility of a chemical reaction.

Answer: C.The rate at which the reaction proceeds.... View Article

A company auditor may be removed in_____.

A company auditor may be removed in general meeting by the company.... View Article

Which among the following is the real product of the honey bee? A. Honey B. Bee wax C. Propolis D. None of these

Answer: B. Bee wax... View Article

When a body is charged by induction, then the body A. becomes neutral B. does not lose any charge C. loses whole of the charge on it D. loses part of the charge on it

Answer: B. does not lose any charge When a body is charged by induction, then the body does not lose any charge.... View Article

A and B can do a piece of work in 30 days, while B and C can do the same work in 24 days and C and A in 20 days. They all work together for 10 days when B and C leave. How many days more will A take to finish the work? A. 18 days B. 24 days C. 30 days D. 36 days

Given, Time taken by A and B to do the work = 30 days A and B one day work = 1/30 Time taken by B and C to do the work = 24 days B and... View Article

If two pipes function simultaneously, a reservoir will be filled in 12 hours. One pipe fills the reservoir 10 hours faster than the other. How many hours will be taken by the second pipe to fill the reservoir.

Let us say, faster pipe takes x hours to fill the reservoir. So, the portion of reservoir filled by faster pipe in one hour = 1/x Time... View Article

A person driving a car with a speed of 72 km/h suddenly sees a boy crossing the road. If the distance moved by car, before the person apply brakes is 5 m, the reaction time of the person is: A. 0.5s B. 0.1s C. 10 s D. 0.25s

Answer: D. 0.25s Given, v = 72 km/hr = (72 x 5)/18 = 20 m/s Time taken to cover 5m distance, t = distance/velocity t = 5/20 = 0.25 sec... View Article

Assuming that water vapour is an ideal gas, the internal energy change (ΔE) when 1mol of water is vapourised at 1 bar pressure and 100°C, (given : molar enthalpy of vapourisation of water at 1 bar and 373K = 41kJ mol–1and R = 8.3J mol–1K–1 ) will be: (a) 4.100 kJ mol-1 (b) 3.7904 kJ mol-1 (c) 37.904 kJ mol-1 (d) 41.00 kJ mol-1

Answer: (c) 37.904 kJ mol-1 H2O(l) ⇌ H2O(g) Given, the internal energy change (ΔE) Molar enthalpy of vapourisation of water at... View Article

In hydrogen atom, the electron makes 6.6 x 10^(15) revolutions per second around the nucleus in an orbit of radius 0.5 x 10^(-10)m. It is equivalent to a current nearly: A. 1Ampere B. 1milliAmpere C. 1 microAmpere D. 1.6 x 10^-19 Ampere

Answer: B. 1milli Ampere Explanation: As we know; I = qV Thus, I = 1.69 x 10-19 x 6.6 x 1015 I = 1.05 x 10-3 or I ≈ 1mA... View Article

A helicopter of mass 1000 kg rises with a vertical acceleration of 15 m/s^2. The crew and the passengers weigh 300 kg. Give the magnitude and direction of the(a) Force on the floor by the crew and passengers.(b) Action of the rotor of the helicopter on the surrounding air.(c) Force on the helicopter due to the surrounding air.

Given, Mass of helicopter , m1=1000kg Mass of the crew & passengers , m2=300kg Upward acceleration of the helicopter , a = 15m/s2 Total... View Article