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Two plane mirrors A and B are aligned parallel to each other as shown in the figure. A light ray is incident at an angle 30° at a point just inside one end of A. The plane of incidence coincides with the plane of the figure. The maximum number of times the ray undergoes reflections (including the first one), before it emerges out, is


A 28
B 30
C 32
D 34

Refer to the given food chain. Select the option which correctly identifies P-T.


AP-Mushroom, Q-Maize plant, R-Rat, S-Snake, T-Kite
BP-Mushroom, Q-Rat, R-Snake, S-Kite, T-Maize plant
CP-Wheat plant, Q-Rat, R-Snake, S-Kite, T-Mushroom
DP-Maize plant, Q-Mushroom, R-Snake, S-Rat, T-Kite

Identify plants P, Q and R and select the correct statement regarding them.

(i) In plant Q, stomata are present only on the upper surface of the leaves.
(ii) Duckweed and water lettuce are other examples of Q type of plant.
(iii) The leaves of plant R do not have stomata.
(iv) Roots of plant P are fixed at the bottom of the pond.

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

The shadow of a pole cast at some time of the day, is shown here.
Which of the following activities would Sukriti most probably be doing at this time?


AGoing for her evening walk
BReturning home from school
CEating her breakfast
DEating her dinner

Study the following informations carefully and answer the question given below:
In a certain code;
(1) 'sti nro kti' means 'speak the truth'.
(2) 'nro bri mti' means 'knowledge is truth'.
(3) 'bri nro zpi' means 'truth knowledge good'.
Which of the above statements is/are required to find the exact code of 'good' ?

A(1) and (2)
B(2) and (3)
C(1) and (3)
DNone of these

Ram paired one living thing and one non-living thing together but in doing so he made an INCORRECT pair.
Select the incorrect pair.

A Bird - Mountain
B Fish - Clock
C Rose plant - Cycle
D River - Book

Read the given statements.
(i) P was used for making Mount Rushmore.
(ii) Q was used for making Taj Mahal.
(iii) R was used for making Red Fort.
Select the option which identifies P–R.

A
B
C
D

Find out the incorrect statement.

A Osmosis is a slow process, occurs down the concentration gradient and does not expend energy.
B Electron microscope uses very high voltage electricity. It uses electromagnets instead of glass lenses and beam of electrons instead of light.
C A semipermeable membrane does not allow both solvent and solute molecules to pass through it.
D Active transport of materials is rapid and usually occurs against the concentration gradient involving carrier proteins and energy in the form of ATP.

A student concludes that the material in a round bowl is liquid. Which statement about the material must be true?

AThe material is clear.
BThe material weighs 1 kg.
CThe material has a temperature of 35°C.
DThe material takes the shape of its container.

Two objects, A and B are thrown upwards simultaneously with the same speed. The mass of A is greater than the mass of B Suppose the air exerts a constant and equal force of resistance on the two bodies, then

AA will go higher than B
BB will go higher than A
CThe two bodies will reach the same height
DNone of these.