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Rohan conducted an experiment as shown here.

What could be the reason for the rise in the level of coloured liquid in the capillary within the test tube in step II?

AWhen test tube was placed in hot water bath, air present within the test tube expanded due to heat.
BWhen test tube was placed in hot water bath, air present within the test tube contracted due to heat.
CWater in the bath contracted due to placement of air-filled test tube in it.
DNone of these

Select the INCORRECT statements.

APlanets and stars do not have light of their own, they shine because they reflect the light of Sun that falls on them.
BRotation of the Earth on its axis causes seasons.
CInner planets are made up of frozen gases whereas outer planets are made up of rocks and iron.
DAll of these.

Cross pollination is the process of

ATransfer of pollen grains from anther of one flower to stigma of other flower on different plant of the same species.
BTransfer of pollen grains from anther of one flower to stigma of the same flower.
CTransfer of pollen grains from anther of one flower to stigma of another flower on different plant of different species.
DBoth A and C

Which of the following options represents the compounds in increasing order of their pH values?

ACopper sulphate, sodium carbonate, zinc sulphate
BAmmonium nitrate, ammonium carbonate, potassium carbonate
CSodium carbonate, zinc sulphate, ammonium chloride
DSodium carbonate, zinc sulphate, ammonium chloride

A lens forms a blurred image of an object on a screen.

How can the image be focused on the screen?

AMove the screen away from the lens and object.
BUse a brighter object at the same position.
CUse a lens of longer focal length at the same position.
DNone of these.

Read the given statements and select the correct option.
Statement 1: In a circuit, surface of the bulb becomes warmer than the connecting wires when the same current flows through them.
Statement 2: A thin and long wire has higher resistance than a thick and short wire.

A Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1.
B Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1.
C Statement 1 is true and statement 2 is false.
D Statement 2 is true and statement 1 is false.

Select the option that correctly fills the boxes X, Y, Z in the given flow chart.


A X - Animal driven land transport, Y - Bullock cart, Z - Tonga
B X - Air transport, Y - Helicopter, Z - Aeroplane
C X - Water transport, Y - Ferry, Z - Ship
D X - Land transport, Y - Bus, Z - Car

A few redox reactions are given as :

Which of the following statements is incorrect about the given redox reactions?

A In reaction I, CuO is acting as an oxidising agent.
B In reaction II, C is oxidised.
C In reaction III, H₂O is reduced.
D In reaction IV, SnCl₂ is acting as an oxidising agent.

Study the given figure carefully. It will be toughest to lift the rock when the force is applied at X, while it will be easiest to do the same when the force is applied at Y. Now, select the correct option regarding X and Y.

Study the given experimental set up. Which of the following statements holds true when the rubber sheet is pulled down?

(i) Air pressure inside the bell jar increases.
(ii) The balloons inside jar expand.
(iii) This is similar to expansion of lungs during inhalation.
(iv) This is similar to contraction of lungs during exhalation.

A (ii), (iii) and (iv) only
B (ii) and (iii) only
C (i) and (iv) only
D (i), (iii) and (iv) only