Question

Theme: Materials, Unit I: Chemical Substances - Nature and
Theme: The World of the Living, Unit II: World of Living;
Theme: Natural Phenomena, Unit III: Natural Phenomena:
GA
1. Define the principal focus of a concave mirror
2. The radius of curvature of a spherical mirror is 20 cm. What is its focal length?
3. Name a mirror that can give an erect and enlarged image of an object
4. The magnification produced by a plane mirror is +1. What does it mean?
5. An object is placed at a distance of 10 cm from a convex mirror of focal length
the position and nature of the image.
6. What do you mean by a balanced chemical equation?
7. What are the implications of a balanced chemical equation?
8. Balance the following chemical equation-
a) HNO 3 + Ca(OH)2 Ca(NO3)2 + H2O
b) NaOH + H2SO4 → Na2SO4 + H2O​

Answer 1

Answer:

1 - Light rays that are parallel to the principal axis of a concave mirror converge at a specific point on its principal axis after reflecting from the mirror. This point is known as the principal focus of the concave mirror.