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A person riding a bicycle observes a passenger sitting in the bus. He finds that the passenger closed his glass window displacing 25 cm in forward direction with a constant speed in 1 sec. Bus overtakes the cyclist in 2 sec. Initially the person was at the middle of the bus as shown in the given figure. Length of the bus is 20 m. If, both the person and bus are moving with constant speed in the same direction, then velocity of the glass window with respect to the person was


A0.25 m/s
B2.5 m/s
C5.25 m/s
D3 m/s

Refer to the given flow chart showing flow of energy in a food chain.

Select the incorrect statements regarding L, M, N and O.
(i) O helps in cleaning of environment as well as recycling of nutrients.
(ii) The role of M comes when plants and animals die.
(iii) L operates at all levels of food chain.
(iv) N eats other animals and gets its food indirectly from L.

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

Select the incorrect match.

ACatalytic converter – Reduces vehicular exhaust
BElectrostatic precipitator – Reduces release of pollutant gases from factories
CMontreal Protocol – Focuses on reducing the levels of CFCs
DNone of these

The given graph represents how three different living organisms (X, Y and Z) cope with the external environmental conditions. Study the graph and select the correct option regarding X, Y and Z.


AX could be sloth.
BY could be sparrow.
CZ could be toucan.
DX could be seal.

When a person moves closer to a plane mirror, the size of his image in the mirror

A Increases
B Remains the same
C Decreases
D First increases and then decreases

Select the incorrect food chain.

APlant → Rabbit → Snake → Peacock
BGrass → Goat → Lion
CPlant seeds → Squirrel → Eagle
DGrass → Mouse → Moth → Snake

Q cannot hear the sound produced by P when the medium between them is __________.

A Oil
B Air
C Brick wall
D Vacuum

The given diagram shows transportation of food and water in a plant.
Select the option that correctly identifies the parts of the plant.

P-------Q-------R

ARoot---Stem---Leaf
BStem---Leaf---Root
CLeaf---Root---Stem
DLeaf---Stem---Root

Study the given diagram which shows X, Y and Z as three states of water. Which arrows, K, L, M and N, represent the processes of melting and boiling?

Melting-----Boiling

AL-----M
BK-----L
CM-----N
DN-----M

________ is a very useful two-way means of audio communication for the people living in different countries.

ANewspaper
BTelephone
CTelevision
DPostcard