P-2 Heredity and Evolution — Science STD 10 — Question

Explain giving one example, how highly reactive metals (which are high up in the reactivity series) are extracted.

1. Which parts of the eye cause rays of light to converge on the retina?
2. Which part causes the greatest convergence?
3. Which part brings the image into sharp focus on the retina? How does it do this?

How does the resistance of a conductor depend on:

1. Length of the conductor?
2. Area of cross-section of the conductor?
3. Temperature of the conductor?

Draw a labelled ray diagram to show how a ray of light passes through a parallel sided glass block:

1. If it hits the glass block at 90° (that is, perpendicular to the glass block).
2. If it hits the glass block at an angle other than 90° (that is, obliquely to the glass block).

Balanced equation

What are the advantages and disadvantages of using a solar cooker?

What is meant by dental caries? How are they caused?

Draw a neat and labelled diagram to show the path of a ray of light in air and glass when the ray is incident obliquely on a glass slab. Show the (i) incident ray (ii) refracted ray (iii) emergent ray (iv) angle of incidence (v) angle of refraction (vi) angle of emergence in the diagram.
(OR)
Draw a neat and labelled diagram to show refraction of light through a glass slab.

Complete the following chart:

	Substance obtained by microbial processing	Roles
(i)	Citric acid	_________________
(ii)	Ascorbic acid	_________________
(iii)	Beta carotene	_________________
(iv)	Glycolipids	_________________
(v)	Vanillin	_________________
(vi)	Xylitol	_________________