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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

Study the given table carefully.

Metals P, Q, R and S could be respectively

A K, Al, Na and Cu
B Cu, Pb, Na and Al
C Ag, Al, Na and Pb
D Cu, Ca, K and Al

Three glass prisms A, B and C of the same refractive index are placed in contact with each other as shown in the figure with no air gap between the prisms.
A ray of light OP passes through the prism assembly and emerges as QR. The condition of minimum deviation is satisfied in the prisms


AA and C only
BB and C only
CA and B only
DA, B and C

Which of the following statements are incorrect?
(i) About 90% of the ozone in our atmosphere is contained in stratosphere.
(ii) The warmest parts of our atmosphere are located in mesosphere.
(iii) Commercial passenger aircrafts usually fly in lower troposphere.
(iv) Satellites orbit around the Earth in thermosphere.

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