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Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupee coin and a one-rupee coin?

Answer: Inertia is the measure of the mass of the body. The greater is the mass of the body; the greater is its inertia and vice-versa. (a) The... View Article

If number of electrons in an atom is 8 and number of protons are also 8, then (i) what is the atomic number of the atom? And (ii) what is the charge on the atom?

Answer: Number of Protons = 8 Number of Electrons = 8 Number of neutrons = 7 Atomic Number = Number of electrons = Number of protons (i) The... View Article

Which option best describes a tropical region? A) Hot and humid B) Moderate temperature, heavy rainfall C) Cold and humid D) Hot and dry

Correct option: A) Hot and humid The climate of the rainforest is hot and humid due to high temperature and plenty of rainfall throughout the... View Article

On what basis would you classify energy sources as (a) renewable and non-renewable? (b) Exhaustible and inexhaustible? Are the options given in (a) and (b) the same?

a) The source of energy that replenishes in nature is known as a renewable source of energy. Sun, wind, moving water, bio-mass, etc. are some of... View Article

What fraction of a clockwise revolution does the hour hand of a clock turn through, when it goesfrom (a) 3 to9 (b) 4 to 7 (c) 7 to10 (d) 12 to9 (e) 1 to 10 (f) 6 to3

Answer: We may observe that in 1 complete clockwise revolution, the hour hand will rotate by 360° The situation from 3 to 9 on the clock the... View Article

Give reasons for the following observation: The smell of hot sizzling food reaches you several metres away, but to get the smell from cold food you have to go close. Why?

The smell of hot sizzling food reaches you several metres away, but you have to go close to get the smell from cold food. Particles of hot... View Article

Give reason for the following observations. (a) Naphthalene balls disappear with time without leaving any solid. (b) We can get the smell of perfume sitting several metres away.

Naphthalene undergoes sublimation easily, i.e., the change of state of naphthalene from solid to gas without the intervention of the liquid... View Article

Three tankers contain 403 liters and 465 liters of diesel respectively. Find the capacity of a container that can measure the diesel of three containers exact number of times.

Answer: Amount of diesel present in the first tank = 403 litres Amount of diesel present in the second tank = 434 litres Amount of diesel... View Article

A vendor supplies 32 liters of milk to a hotel in a morning and 68 liters of milk in the evening. If the milk costs Rs. 15per liter, how much money is due to the vendor per day?

Given A vendor supplies 32 litres of milk to a hotel in the morning and 68 litres of milk in the evening. Find out We need to find if the milk... View Article

A sonar device on a submarine sends out a signal and receives an echo 5 s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m.

Time is taken to hear the echo, t = 5 s Distance of the object from the submarine, d = 3625 m Total distance travelled by the sonar waves... View Article

No matter how far you stand from a mirror, your image appears erect. The mirror is likely to be (a) Plane Option (b) Concave Option (c) Convex Option (d) Either plane or convex

Correct option: (d)Either plane or convex In-plane mirrors, the image is always erect. In convex, an image formed is virtual and erect for all... View Article

Draw a schematic diagram of a circuit consisting of a battery of three cells of 2 V each, a 5 Î resistor, an 8 Î resistor, and a 12 Î resistor, and a plug key, all connected in series.

Three cells of potential 2 V, each connected in series therefore the potential difference of the battery will be 2 V + 2 V + 2 V = 6V. The... View Article

Which statement regarding an orbital is true? i) There are three lobes in the d orbitals. ii) There are four sets of p orbitals. iii) K,L,M,N indicate the shells. iv) None of the above

K, L, M, N indicate the shells. K denotes the first shell (or energy level), L the second shell, M, the third shell, etc. In other words, the... View Article

Find the L.C.M of the following numbers: (a) 9 and 4 (b) 12 and 5 (c) 6 and 5 (d) 15 and 4 Observe a common property in the obtained L.C.Ms. Is L.C.M. the product of two numbers each case?

Answer: In Mathematics, LCM (The Least Common Multiple) of any two is the value that is evenly divisible by the two given numbers. (a) 9 and 4... View Article

How many right angles do you make if you start facing: (a) South and turn clockwise to west? (b) North and turn anti-clockwise to east? (c) West and turn to west? (d) South and turn to north?

(a) South and turn clockwise to west: One right-angle (b) North and turn anti-clockwise to east: Three right-angles (c) West and turn to west:... View Article

What part of a revolution have you turned through if you stand to face: (a) East and turn clockwise to facenorth? (b) South and turn clockwise to faceeast? (c) West and turn clockwise to faceeast?

Answer: Here, the turn from east to the south is one right angle, from south to west is one right angle and from west to the north is one... View Article

A ball is gently dropped from a height of 20 m. If its velocity increases uniformly at the rate of 10 m sˆ’2, with what velocity will it strike the ground? After what time will it strike the ground?

Answer: Let us assume, the final velocity with which the ball will strike the ground be 'v' and the time it takes to strike the ground be 't'.... View Article

A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is (i) pushed into the coil, (ii) withdrawn from inside the coil, (iii) held stationary inside the coil?

(i) The needle of the galvanometer shows a momentary deflection in a particular direction. (ii) The needle of the galvanometer shows a... View Article

Choose the correct option from the following: Which part of the plant takes in carbon dioxide from the air for photosynthesis? (A) Root hair (B) Stomata (C) Leaf veins (D) Sepals

Answer: (B) Stomata The part of the plant that takes in carbon dioxide from the air for photosynthesis stomata. Stomata are the pores present... View Article

Which of the following are chemical changes? (a) Growth of a plant (b) Rusting of iron (c) Mixing of iron filings and sand (d) Cooking of food (e) Digestion of food (f) Freezing of water (g) Burning of a candle.

Answer: If the chemical composition is changing, then it is a chemical change, and if the chemical composition is remaining the same, then it is... View Article

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