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Rohit took a burning candle and covered it with a glass chimney as shown in figure I. He took another burning candle and slid a thin tin plate with a hole in the middle just below the flame and above the melted wax as shown in figure II. Then, he took the third candle and covered it with a glass chimney which was kept on the wooden blocks as shown in figure III.

Which of the following observations is correct?

A Smoke is produced in candle III due to less supply of air.
B Candles I and III burn freely.
C Tin plate conducts more heat towards the wick and hence, candle II becomes brighter.
D The flame flickers and produces smoke in candle I.

The following is the distance-time table of a moving car on a straight road.

Read the given statements and select the correct option.

AThe average speed of the car is 36.5 km/h.
BThe speed of the moving car between 11:25 am to 11:40 am is 4.4 m/s.
CThe moving car is in uniform motion.
DThe speed of the moving car between 10:40 am to 10:50 am is 19 m/s.

Refer to the given figure illustrating different types of pollination in plants.

Rohan planted three different types of plants (P, Q and R) in his garden whose seeds are dispersed by explosive mechanism. The given figure shows distribution of these plants in Rohan’s garden over a time period.

Select the correct statement regarding it.

AP undergoes process X only whereas Q and R undergo processes Y and Z only.
BP could be a male plant of species undergoing only process Z whereas Q and R plants could undergo any of the processes X, Y or Z depending upon the type of species.
CP is a plant undergoing only process Y so its population does not increase with time in the absence of other plant of the same species in the garden.
DPlants Q and R are unisexual plants which can undergo only processes X and Y thereby assuring fertilisation and seed setting in absence of other plants of their species.

The given graph shows heart rates of three persons X, Y and Z under different conditions over time. Select the correct option regarding it.


APerson X is a dead person whereas persons Y and Z are suffering from different heart diseases.
BPerson X is sleeping, person Y is exercising whereas person Z is having irregular heartbeat due to some heart dysfunction.
CPerson X is going through a heart attack whereas person Z has healthy heart showing changes in heart rates while walking.
DNone of these

Study the given table and select the correct option.

L-----M-----N-----O

ASpirogyra---Spirogyra---Mushroom---Begonia
BHydra---Rhizopus---Spirogyra---Chrysanthemum
CSpirogyra---Rhizopus---Bryophyllum---Dahlia
DAsparagus---Yeast---Spirogyra---Rhizopus

A few substances are listed in the box.

Which of the following statements are correct regarding these substances?
I. Solutions (i), (ii), (iv) and (vii) change the colour of methyl orange indicator to red.
II. Solutions (ii), (iii) and (v) show no change in colour with phenolphthalein indicator.
III. Solutions (vi) and (vii) show no change in colour of blue litmus solution.
IV. China rose indicator turns magenta in solutions (iii) and (v).

AI and III only
BIII and IV only
CII, III and IV only
DI, III and IV only

Which of the following statements is not correct in case of an electric fuse?

AIt is a safety device which prevents damages to electrical circuits and possible fires.
BIts working is based on the principle of heating effect of electric current.
CIf a proper fuse is inserted in a circuit it will blow off if current exceeds the safe limit.
DNone of these.

Select the correct statement(s).
I. Turmeric paper can be used to distinguish between an acidic and a neutral material.
II. Hydrochloric acid burns the skin and sodium hydroxide is harsh on skin but the product formed by neutralisation reaction between two is edible.
III. When sulphuric acid is mixed with lime water, sodium sulphate is formed which is a neutral salt.
IV. Reaction between an acid and a base always results in the formation of a neutral salt.
V. Aqua regia contains hydrochloric acid and nitric acid in the ratio 3:1.

AIII only
BII and V only
CI, III and V only
DIV and V only

Study the given table.

Which of the following is correct regarding X, Y and Z.

AX could be potato whereas Y could be banana.
BY could be radish whereas Z could be carrot.
CX could be onion whereas Z could be mango.
DAll of these

Read the following statements carefully and select the option that correctly identifies them as true (T) and false (F) ones.
I. During extreme heat of summer, at some places dry grass catches fire which spreads to trees, and very soon the whole forest is on fire.
II. Goldsmiths blow the innermost zone of a flame with a metallic blow-pipe for melting gold and silver.
III. Combustion is a chemical process in which a substance reacts with carbon dioxide to give oxygen and heat.
IV. The highest temperature at which a substance catches fire is called its ignition temperature.
V. Carbon dioxide is used to extinguish fires involving oil and petrol.