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Which of the following is correct?

A Water can be used for extinguishing fires caused due to electrical faults.
B Carbon is a non-metal so it cannot be used in electrolytic cell.
C A liquid conducts electricity because of the presence of ions.
D Pure water forms ions to conduct electricity.

A housewife was preparing hot meal for her family. She accidentally placed her fingertip into some boiling soup, but quickly withdrew it. She felt significant pain in the finger immediately after that. Which of the following is the most likely explanation for this time lag?

A The withdrawal of her finger is a reflex action that is triggered more quickly than the transmission of information related to pain stimulus to her brain.
B The pain receptors present on her finger skin are less efficient, so information regarding pain is transmitted to brain at a slower rate as compared to that of heat.
C The withdrawal of her finger is controlled by brain so it occurs very fast whereas feeling of pain is a reflex action controlled by spinal cord so it takes comparatively much more time.
D None of these

Seema took four syringes with stoppers inserted at their nozzles. Each syringe contains a different substance. All syringes are completely filled with their contents such that their plungers are pulled out to the maximum. Which of the following plungers can be pushed in easily?

A
B
C
D

Which of the following statement(s) is/are incorrect?
(i) Two thin woollen sweaters are warmer than a thick woollen sweater.
(ii) It saves fuel if we cook food in a vessel which is blackened at the bottom and polished from the sides.
(iii) The cable wires between two poles are left loose because in summers, the wires do not break on expanding.

A Only (i) and (iii)
B Only (ii) and (iii)
C Only (iii)
D Only (i)

Select the odd one out.

A
B
C
D

Which of the following is the correct difference between weaving and knitting?

A Weaving is done with machine while knitting is done with hand only.
B Weaving uses two sets of yarn while knitting involves only one yarn.
C Weaving is done for silk only while knitting is done for wool only.
D All of these

Sohan has three identical roses of different colours; red, yellow and pink. He shines a torch on the three roses one-by-one and gets a shadow on the wall in each case. Richa who is observing the shadows formed on the wall can

ADistinguish shadow of the red rose only
BDistinguish shadows of the red and yellow roses only
CDistinguish shadows of all the three roses
DNever distinguish the shadows of the three roses.

Study the given diagrams showing the cross-section of two flowers. Which of the following statements is/are correct regarding them?

(i) Both flowers will produce female gametes.
(ii) Flower X is a bisexual flower and flower Y is a male flower.
(iii) Self pollination can take place in flower Y only.

A(i) only
B(iii) only
C(i) and (ii)
DNone of these

On a cold day, it is hard to open the metallic lid of a tight glass container. But when you gently heat the neck you can easily open the lid. Why?

AOn heating, glass expands and lid contracts.
BOn heating, lid expands more than the neck and thus slides easily.
CNeck becomes slippery on heating.
DLid of the bottle cannot bear the heat.