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Distinguish between desire and demand

Desire 1. Desire simply refers to the mere wish of a person to have a particular commodity, irrespective of the fact whether one can buy it or... View Article

A refrigerator whose coefficient of performance K = 5, extracts heat from the cooling compartment at the rate of 250 J/cycle. What is the work done per cycle to operate the refrigerator? How much heat is discharged per cycle to the room which acts as the high temperature reservoir? (A) 50 J (B) 200 J (C) 300 J (D) None

Work done per cycle W = Q2/K Given Q2 = 250 J On substituting, we get, W = 250/5 W = 50 J Hence, 50 J of work is needed to be done per cycle... View Article

A 100 mL solution of 0.1 N HCl was titrated with 0.2 N NaOH solution. The titration was discontinued after adding 30 ml of NaOH solution. The titration was completed by adding 0.25 N KOH solution. The volume of KOH required for completing the titration is: (a) 70 mL (b) 32 mL (c) 35 mL (d) 16 mL

In the neutralization of acid and base N x V of both must be equivalent N x V of HCl = 0.1 x 100 = 10 N x V of NaOH = 0.2 x 30 = 6 To obtain 10N... View Article

Which of the following secretions does not contain enzymes? (a) Bile (b) Pancreatic juice (c) Intestinal juice (d) Saliva

Bile Bile does not contain any enzymes like other secretions from the gastrointestinal tract but is very essential in the process of digestion.... View Article

Three rigid rods are joined to form an equilateral triangle ABC of side 1 m. Three particles carrying charges 20μC each are attached to the vertices of the triangle. The whole system is at rest in an inertial frame. The resultant force on the charged particle at A has the magnitude. (a) zero (b) 3.6 N (c) 3.6 √3 N (d) 7.2 N

zero We know that, Fnet = ma a = acceleration of the charged particle at A is zero Hence, we can say that net force will also be zero ⇒Fnet... View Article

To increase the range of a voltmeter we need to connect a suitable (A) high resistance in series (B) high resistance in parallel (C) low resistance in series (D) low resistance in parallel

High resistance in series The range of the voltmeter can be increased by increasing the resistance. This can be done by connecting a resistor in... View Article

The direction of acceleration due to gravity is always vertically downward. State whether true or false (A) True (B) False

True Acceleration due to gravity (g = 9.8 m/s2)always acts in the downward direction. Therefore, the given statement is true So, the correct... View Article

The additive inverse of 17 is (A) -17 (B) 17 (C) 1/17 (D) -1/17

-17 Since 17 + (-17) = 0 where 0 is the additive identity Therefore, the additive inverse of 17 is -17 So, the correct option is (A)... View Article

Inflating a balloon seems to violate Boyle’s law. Why?

Boyle’s law states that the volume of a given mass of a dry gas is inversely proportional to its pressure at a constant temperature.... View Article

State three differences between water and air

Water 1. The components of water are hydrogen and oxygen which are chemically combined in a fixed ratio of 1:8 by mass 2. The chemical... View Article

How do you find the exact value of cos (-2π/3)?

We know that, cos (-θ) = cos θ Hence, cos (-2π/3) = cos (2π/3) = cos [π - (π/3)] = -cos (π/3) [Since cos(1800 -... View Article

Turpentine oil in paints is used as a (a) Thinner (b) Vehicle (c) Base (d) Drier

Thinner Turpentine is a substance characteristic of pine trees and other conifers, is composed of a mixture of resins and volatile oils. Pinus... View Article

Find out the wrong term 3, 2, 8, 9, 13, 22, 18, 32, 23, 42 (a) 8 (b) 9 (c) 13 (d) 22

The given sequence is a combination of two series as shown below First: 1, 3, 8, 13, 18, 23 Second: 2, 9, 22, 32, 42 Clearly, the pattern in... View Article

What was the life expectancy in India during British rule? (a) 30 years (b) 32 years (c) 35 years (d) 40 years

As per the Government issued data, life expectancy during British India was 32 years and today it is 68 years. Therefore, the correct option is (b)... View Article

State the main function of lymphocytes

Lymphocytes play a major role in adaptive immunity. The B cells are responsible for humoral immunity and T cells are required for the... View Article

Newtons law of cooling is a special case of (a) Kirchoff’s law (b) Weins law (c) Stefan-Boltzmanns law (d) Plancks law

Newtons law of cooling is a special case of Stefan's-Boltzmann law. It is derived from Stefan's law. Hence, the correct option is (c)... View Article

In soil, water available to plants roots is (a) Hygroscopic water (b) Capillary water (c) Gravitation water (d) Colloid water

Capillary water The water present in narrow soil spaces is called capillary water, available to plant roots for absorption. It is found in... View Article

Refractive index depends on the __________of light

Refractive index depends on the wavelength of light The change in the speed of light causes it to bend which is simply known as refraction.... View Article

In an n-p-n transistor circuit, the collector current is 10 mA. If 90% of the electrons emitted reach the collector: (a) The base current will be 1 mA (b) The base current will be -1 mA (c) The emitter current will be 9 mA (d) The emitter current will be 15 mA

Given Collector current, Ic = 10 mA According to the question, Ic = 90% of IE 10mA = (90/100)IE IE = (10 x 10)/9 We get, IE = 11 mA Now, Base... View Article

What is the absolute mass and charge of a proton?

Mass of Proton - The mass of a proton is equal to that of the hydrogen atom. A hydrogen atom consists of one electron and one proton. As the mass... View Article