(a) The distance between Earth and Moon is 384,000,000 m.
= 3.84 × 108 m
(b) Speed of light in vacuum is 300,000,000 m/*
= 3 × 108 m/*
(c) Diameter of the Earth is 1,27,56,000 m.
1.2756 × 107 m
(d) Diameter of the Sun is
1,400,0, 000m.
1.4 × 109m
(e) Number of average stars in a galaxy = 100,000,000m.
= 1 × 1011 m
(f) The universe is estimated to be about 12,000,000,000 years old.
= 1.2 × 1010 years old
(g) The distance of the Sun from the centre of the Milky Way Galaxy is estimated to be 300,000,000,000, 000, 000 m.
= 3 × 1020 m
(h) 60,230,000,000,000,000,000,000 molecules are contained in a drop of water weighing 1.8 gm.
= 6.023 × 1022 molecules
(i ) The earth has 1,353,000,000 cubic km of sea water.
= 1.353 × 109 cubic km
(j) The population of India was about 1,027,000000 in March, 2001.
= 1.027 × 109
