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The process of conversion of sugar into alcohol is called (i) nitrogen fixation (ii) moulding (iii) fermentation (iv) infection

The correct answer is (iii) fermentation Fermentation is the process which is carried by anaerobic respiration of microorganism which leads to... View Article

What will happen if: (a) we go on cutting trees. (b) the habitat of an animal is disturbed. (c) the top layer of soil is exposed.

(a) If we go on cutting trees, then: Earth will lose its top fertile soil layer and get converted into a desert. The ecological balance will... View Article

Write down the names of compounds represented by the following formulae: (i) Al₂(SO₄)₃(ii) CaCl₂ (iii) K₂SO₄ (iv) KNO₃ (v) CaCO₃

(i) Al2(SO4)3 Aluminium sulphate: Aluminium sulfate is an industrial chemical used as a flocculating agent in the purification of drinking water... View Article

Say true or false: (a) Two diameters of a circle will necessarily intersect (b) The Centre of a circle is always in its interior.

(a) True. The diameter of the circle is the longest chord and is always in the centre in horizontal or vertical of the circle (b)True. The Centre... View Article

A sound wave travels at a speed of 339 m/s. If its wavelength is 1.5 cm, what is the frequency of the wave? Will it be audible?

Answer: Speed of sound (v) = 339 ms-1 Wavelength of sound (λ) = 1.5 cm λ = 0.015 m Speed of sound = Wavelength x Frequency Frequency = Speed... View Article

Medicine is packed in boxes, each weighing 4 kg 500 g. How many such boxes can be loaded in a can which cannot carry beyond 800kg?

Given that Medicines are packed in boxes. One box weighs 4kg 500g. Find out We need to find many of the numbers of boxes that can be loaded in... View Article

Which of the following numbers are co-prime: (a) 18 and 35 (b) 15 and 37 (c) 30 and 415 (d) 17 and 168 (e) 216 and 215 (f) 81 and 16

Answer: A Co-prime number is a set of numbers or integers which have only 1 as their common factor, i.e. their highest common factor (HCF) will... View Article

Which of these are not accessory glands? i) Prostate gland ii) Seminal vesicle iii) Cowper’s gland iv) Sebaceous glands are oil glands

The others are accessory glands, which add various secretions to the sperms, thus forming semen. Sebaceous glands are oil glands present in the... View Article

What are the environmental consequences of the increasing demand for energy? What steps would you suggest to reduce energy consumption?

Today in this era of globalisation and industrialisation the demand for energy is at the peak. To initiate a small task energy is the prior... View Article

The xylems in plants are responsible for(a)Transport of water (b)Transport of food (c) Transport of amino acids (d) Transport of oxygen

Correct option: a) Transport of water The xylems in plants are responsible for the transport of water. Xylem is a type of tissue in vascular... View Article

A doctor has prescribed a corrective lens of power +1.5D. Find the focal length of the lens. Is the prescribed lens diverging or converging?

Given P = +1.5 D Find out We need to find out the focal length of the given lens Solution We know that f = 1/P Where, f is the focal... View Article

Find the value of the following: (a) 297 x 17 + 297 x 3 (b) 54279 x 92 + 8 x 54279 (c) 81265 x 169 – 81265 x 69 (d) 3845 x 5 x 782 + 769 x 25 x 218

We can determine the product of given set of numbers by the Distributive Property. Distributive Property states that “when a factor is... View Article

What is (a) the highest, (b) the lowest total resistance that can be secured by combinations of four coils of resistance 4 Ω, 8 Ω, 12 Ω, 24 Ω?

There are four coils of resistances 4 Ω, 8 Ω, 12 Ω and 24 Ω, respectively. (a) If these coils are connected in series, then the equivalent... View Article

A tadpole develops into an adult frog by the process of: (a) fertilization Option (b) metamorphosis (c) embedding (d) budding

Correct Option: (b) metamorphosis. A tadpole develops into an adult frog by the process of metamorphosis. Metamorphosis is the change of shape... View Article

Give the names of the elements present in the following compounds: (a) Quick lime (b) Hydrogen bromide (c) Baking powder (d) Potassium sulphate

Compounds Elements Quick lime Calcium and oxygen Hydrogen bromide Hydrogen and bromine Baking powder Sodium, Hydrogen, Carbon and... View Article

As compared to Potassium, Sodium has: i) Lower electronegativity ii) Lower melting point iii) Higher ionization potential iv) Greater atomic radius

The correct option is iii) Higher ionization potential. The potential energy of Sodium is higher than Potassium because of the smaller atomic... View Article

Write the chemical formulae of the following: (a) Magnesium chloride (b) Calcium oxide (c) Copper nitrate (d) Aluminium chloride (e) Calcium carbonate

Answer: The chemical formula of a compound is a symbolic representation of its chemical composition. Chemical formulae provide insight into the... View Article

Shekhar is a famous cricket player. He has so far scored 6980 runs in test matches. He wishes to complete 10,000 runs. How many more runs does he need?

Given Runs to comlete = 10,000 Runs scored= 6,980 Find out We have to determine how many more runs does he need Solution To determine how... View Article

Find the number of right angles turned through by the hour hand of a clockwhen it goes from: (a) 3 to 6 (b) 2 to 8 (c) 5 to11 (d) 10 to1 (e) 12 to 9 (f) 12 to 6

Answer: The hour hand of the clock revolves by 360 degree or 4 right angles in 1 complete round. The hour hand of a clock revolves by 90... View Article

A submarine emits a sonar pulse, which returns from an underwater cliff in 1.02 s. If the speed of sound in salt water is 1531 m/s, how far away is the cliff?

Given Time taken by the sonar pulse to return, t = 1.02 s Speed of sound in saltwater, v = 1531 ms-1 Find out We have to determine how far... View Article