Rahul adds aqueous solution of barium chloride to an aqueous solution of sodium sulphate. What would he observe?

i. Define the following terms in the context of spherical mirrors:

A. Pole

B. Centre of curvature

C. Principal axis

D. Principal focus

ii. Draw ray diagrams to show the principal focus of a:

A. Concave mirror

B. Convex mirror

iii. Consider the following diagram in which M is a mirror, P is an object and Q is its magnified image formed by the mirror.

State the type of the mirror M and one characteristic property of the image Q.

OR

i. Draw a ray diagram to show the formation of image by a convex lens when an object is placed in front of lens between its optical centre and principal focus.

ii. In the above ray diagram mark the object-distance (u) and the image-distance (v) with their proper signs (+ve or –ve as per the new Cartesian sign convention) and state how these distances are related to the focal length (f) of the convex lens in this case.

iii. Find the power of a convex lens which forms a real, and inverted image of magnification-1 of an object placed at a distance of 20 cm from its optical center.

i. Two identical resistors each of resistance 10Ω are connected in

A. Series

B. Parallel to a 6 V battery

Calculate the ratio of power consumed in the combination of resistors in two cases.

ii. Draw the circuit diagram of the two cases.

Ans. i. 4 : 1

A strip of copper was placed in a beaker containing zinc sulphate solution. On observing the strip next day, was there any colour change in the strip?

To prepare a good temporary mount of the petunia leaf peel showing many stomata, from where does the student has to get the peel?

OR

A student sets up the apparatus for the experiment to show that CO₂ is released during respiration. After 2 hours, what would he observe?