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The diagram given below shows an object O and its image I. Without actually drawing the ray diagram, state the following: (i) Type of lens (Converging / Diverging) (ii) Name two optical instruments where such an image is obtained. (iii) List three characteristics of the image formed if this lens is replaced by a concave mirror of focal length ‘f’ and an object is placed at a distance ‘f/2’ in front of the mirror.

(i) Type of lens is Converging Lens (Convex lens) because the image is magnified (larger than the object) and on the same side as that of the... View Article

A green stemmed rose plant denoted by GG and a brown stemmed rose plant denoted by gg are allowed to undergo a cross with each other. (a) List your observations regarding (i) Colour of stem in their F1 progeny (ii) Percentage of brown stemmed plants in F2 progeny if F1 plants are self pollinated. (b) Based on the findings of this cross, what conclusion can be drawn? (iii) Ratio of GG and Gg in the F2 progeny.

a) i) Green ii) 25% iii) 1:2 b) The conclusion is that both the gametes are showing it’s expression in the F2 generation because we are getting... View Article

Study the data of the following three categories A, B and C. (i) From the given three categories A, B and C, pick the one which forms Dobereiner’s Triads. (ii) Why did Mendeleev placed elements of category A, B and C in three different groups? (iii) Is Newland law of octaves applicable to all the three categories? Give reason to justify your answer.

(i)Dobereiner stated in his law of triads that the arithmetic mean of the atomic masses of the first and third element in a triad would be... View Article