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Read the following statements carefully.
W : I am very reactive and catch fire if exposed to air. To prevent this, I am stored in water.
X : I am a good conductor of heat and acquire a reddish-brown coating on exposure to moist air.
Y : I am soft and have dull appearance. I form acids on reacting with oxygen and water.
Z : I am malleable, ductile and acquire a dull green coating on exposure to moist air.
Identify W, X, Y and Z.

--------W---------------X-------------Y--------------Z
APhosphorus--Copper------Sulphur--------Iron
BPhosphorus--Iron----------Sulphur--------Copper
CSulphur------Iron-----------Phosphorus---Copper
DCopper------Phosphorus---Iron------------Sulphur

Equal forces F act on isolated bodies A and B as shown in the figure. The mass of B is three times that of A. The magnitude of the acceleration of A is


AThree times that of B
B that of B
CNine times that of B
D that of B.

Match column I and column II and select the correct option from the given codes.


AP-(ii), Q-(ii), R-(iii)
BP-(ii), Q-(i), R-(iii)
CP-(i), Q-(iii), R-(ii)
DP-(i), Q-(i), R-(ii)

The numerical ratio of distance to displacement is ________.

A Always equal to one
B Always less than one
C Always greater than one
D Equal to or more than one.

Read the passage carefully and answer the following questions.
Two tuning forks, A and B vibrate with frequencies in the ratio 2 : 7 and their wavelengths in the ratio 3 : 4 respectively. Both the tuning forks are placed in different media.
The tuning fork A produces relatively

A Shrill sound than tuning fork B
B Flat sound than tuning fork B
C Louder sound than tuning fork B
D Sound of more wavelength than that of tuning fork B.

You need to put a metal rod into a hole in a metal cylinder. It is too tight. Which would be the best strategy to make the rod fit?


AHeat the rod and cylinder
BCool the rod and cylinder
CHeat the rod and cool the cylinder
DCool the rod and heat the cylinder

An iron ring is heated. Which of the following statements is/are correct?
I. The ring expands.
II. The ring almost comes to the same size on cooling.
III. The change occurring in this case is reversible.
IV. The ring changes its shape and the change cannot be reversed.

AI only
BI, II and III only
CIV only
DII and III only

Study the given classification table and identify objects P, Q and R.

Study the given Venn diagram. Identify P, Q, R and S and select the incorrect statement regarding them.


AP could be an organism that helps in recycling of nutrients in the biosphere.
BQ could be an organism that lives in both aquatic as well as terrestrial habitat.
CS may possess thick layer of fat under the skin which is called blubber.
DR could be a warm blooded animal that possesses hard waterproof scales.

Identify the elements W, X, Y and Z from the given information.
W : Best conductor of electricity
X : Essential component of haemoglobin
Y : Hardest natural substance
Z : Source of energy in sun and stars