Science and Technology

Why is sea-urchin kept in phylum Echinodermata?

(i) Because their bodies are externally covered by hard calcareous spines.

(ii) Because they have muscular feet to help in swimming in water and gliding on the surface.

(iii) Because their body is soft.

(iv) Because it has tentacles on the head.

Which of the following statements is correct about queen bee?

(i) Queen bee feeds honey and bread to larvae.

(ii) Queen bee makes the hive warm.

(iii) A hive has a large number of queen bees.

(iv) In a hive the queen bee lives the longest.

Which of the following plants has antioxidant, antimicrobial property as well as the capacity to relieve stress, depression and anxiety?

(i) Turmeric

(ii) Asiatic pennywort

(iii) Gurjo

(iv) Neem

What will be the weight of a man on the Moon, if his weight on the Earth is 750 N? (Acceleration due to gravity of the Moon = $1.63\text{ m/s}^2$)

(i) 124.7 N

(ii) 125 N

(iii) 126.8 N

(iv) 127.8 N

Which of the following phenomena is based on the high specific heat capacity of water?

(i) The temperature of water in ocean does not vary much between day and night.

(ii) Even when the surface of Mountain Lake freezes in winter, fish don't die.

(iii) Water pipes burst in winter.

(iv) Temperature of water remains constant while boiling.

Which of the followings correctly describes the properties of an image formed by a convex lens when object is placed at between 'f' and '2f'?

(i) Virtual, erect and diminished

(ii) Virtual, inverted and magnified

(iii) Real, inverted and magnified

(iv) Real, erect and magnified

A transformer has 6,000 turns in the primary coil and 1,000 turns in the secondary coil. Calculate the secondary voltage if the primary voltage is 210 V.

(i) 25 V

(ii) 35 V

(iii) 45 V

(iv) 55 V

Which substance is the product 'Z' in the given chemical reaction? $\text{CO}_2 + \text{H}_2\text{O} \rightarrow \text{Z}$

(i) HCO

(ii) $\text{H}_2\text{CO}_2$

(iii) $\text{H}_2\text{CO}_3$

(iv) COOH

Which of the following represents alkene?

(i) $\text{C}_nH_{2n+2}$

(ii) $\text{C}_nH_{2n-2}$

(iii) $\text{C}_nH_{2n-1}$

(iv) $\text{C}_nH_{2n}$

Which of the following compounds is used to ripen fruits?

(i) Sodium carbonate

(ii) Calcium carbonate

(iii) Calcium carbide

(iv) Sodium sulphate