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Fill in the blanks:(i) The average weather taken over a long time is called (fill in the blank). (ii) A place receives very little rainfall and the temperature is high throughout the year, the climate of that place will be (fill in the blank)and (fill in the blank). (iii) The two regions of the earth with extreme climatic conditions are (fill in the blank) and (fill in the blank).

(i) The average weather taken over a long time is called climate. (ii) A place receives very little rainfall and the temperature is high... View Article

Which blood vessel carries blood from the kidneys back to the heart?

The renal vein leaves the kidneys and carries the blood back to the heart. Since the kidneys extract the nitrogenous metabolic wastes, the renal... View Article

Explain anti-Markovnikov’s rule.

Anti-Markovnikov rule explains the regiochemistry where the substituent is bonded to a less substituted carbon, rather than the more substitued... View Article

The length of a long rod is measured first by using pace-span and then, by using foot-span of a person. For the person, the length of one pace-span is four times the length of one foot-span. If the length of the rod is 6 pace-spans, then what is the length of the rod in terms of foot-span?

It is given that the length of one pace-span is four times the length of one foot-span. Therefore, 1 pace-span = 4 foot-spans. Also, it is given... View Article

What are the factors that affect the rate of corrosion?

Answer: Corrosion is defined as the natural process that causes the conversion of pure metals to undesirable substances when they react with... View Article

There are four mirrors labelled as I, II, III, and IV. Mirrors I and IV can form virtual and small images only. Mirror III can form an image that can be obtained on a screen. Mirror II cannot form real images of objects. Which of the given mirrors can form an inverted image of the object?”

The image formed by mirror III can be obtained on a screen. Hence, mirror III can form a real image. This implies that mirror III is a concave... View Article

An object experiences a net zero external unbalanced force. Is it possible for the object to be travelling with a non-zero velocity? If yes, state the conditions that must be placed on the magnitude and direction of the velocity. If no, provide a reason.

Yes, an object may travel with a non-zero velocity even when the net external force on it is zero. An object moving in some direction with... View Article

Why are ionic compounds are soluble in water but insoluble in kerosene?

The ionic compounds are held together by ionic bonds and categorized as ionic compounds. The crystalline solids are formed by neatly packed ions... View Article

A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force. Let us take it that the force acts on the object through the displacement. What is the work done in this case?

Answer: When a force F acts on an object to move it in its direction through a distance S, the work is done The work on the body is done by... View Article

Process involving movement of substances against the concentration gradient using ATP.

Active transport is the process involving movement of substances against the concentration gradient using ATP. The reason the process is referred... View Article

Name sources of energy that are not ultimately derived from the sun’s energy? a)Bio-mass b)Geothermal energy c)Wind energy d)Nuclear energy

The correct option is d) Nuclear energy The energy that is required for fusing two nuclei is provided by the fission reactions. There is no... View Article

Explain why coils of electric toasters and electric irons made of an alloy rather than a pure metal?

Coils of electric toasters and electric irons made of an alloy rather than a pure metal due to the following reasons: The resistivity of an... View Article

What is the sum of the numbers 6.68 and 0.8?

During addition, the result cannot have more digits to the right of the decimal point than either of the original numbers. Since there is only 1... View Article

How are the alveoli designed to maximize the exchange of gases?

Answer: The human respiratory tract is made up of the nostril, larynx, nasal chamber, pharynx, trachea, epiglottis, alveoli, bronchioles,... View Article

The root mean square (R.M.S.) Speed V of the molecules of an ideal gas is given by the expressions, v = sqrt (3RT/M) and v = sqrt (3KT/m) where R is universal gas constant, T is the absolute (Kelvin) temperature M is the molar mass, K is Boltzman’s constant and M is the molecular mass. The R.M.S. speed of oxygen molecules (O2) at temperature T1 is V1. When the temperature is doubled, if the oxygen molecules are dissociated into atomic oxygen, what will be R.M.S. speed of oxygen atoms? (Treat the gas as ideal).

We have V1 = sqrt (3RT1/M) or V1 = sqrt (3kT1/m) on dissociation the molar mass as well as the molecular mass gets halved. Using the second... View Article

Select the incorrectly matched pair with regard to the C4 cycle. (1) Primary CO2 fixation product – PGA (2) Site of initial carboxylation – Mesophyll cells (3) Primary CO2 acceptor – PEP (4) C4 plant – Maize (5) Location of enzyme RuBisCO – Bundle sheath cells

Answer: (1) Primary CO2 fixation product - PGA The primary CO2 fixation product in C4 plants is oxaloacetic acid, which is converted to malic... View Article

An electric lamp of 100 Ohms, a toaster of resistance 50 Ohms, and a water filter of resistance 500 Ohms are connected in parallel to a 220 V source. What is the resistance of an electric iron connected to the same source that takes as much current as all three appliances, and what is the current through it?

Given parameters: Resistance of electric lamp (R1) = 100 Ω Resistance of toaster (R2) = 50 Ω Resistance of water filter (R3) = 500 Ω A... View Article

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