Enfant India International
school
Class -8th
Sub. - Physics
M.M.-20
Section -A
1. Fill in the blanks :
(1×5=5)
(a) Heat is ______ during boiling process.
(b) Evaporation causes ______ of the surrounding.
(c) Liquids have only ______ expansion.
(d) The _____ of a spherical mirrior is called its pole .
(e) Water is optically denser than ______ but optically rarer as compared to ________.
2. Define the following : (1×5=5)
(a) Refractive index
(b) Refraction of light
(c) Principal axis
(d) Radius of curvature
(e) Dispersion of light
Section-B
3. Answer these
questions:
(2×5=10)
(a) State any one application of thermal expansion of liquids.
(b) Give any three practical applications of thermal expansion of solids .
(c) What is a spherical mirror ?what are its two kinds ?
(d) What is refraction of light ?
(e) State the two laws of refraction ?
