sure questions in competative exam which confuse everyboby....?

Question

which of the following is more elastic(a)glass(b)rubber(c)stainless steel(d)tungston.speed of light will be minimum when passing through(a)glass(b)vaccum(c)water(d)air.another one is concerning the properties of sound waves.It is said that speed of sound depends upon elasticity,density,temperature and motion of particles of the medium of propagation.higher tha elasticity of a medium greater is the speed of the sound.i also want to know whether moist air or dry air have high density?whether speed of sound increases or decreases with high density?what is the case of light waves.please answer me .

Answer 1

RUBBER

Answer 2

i) tungston -a substance is more elastic if it can get back to its own shapa after the force which tries to deform it is removed

ii)glass - because it is a much denser medium

iii)Moist air has higher density and speed of sound increases with higher density, so the speed of sound in moist air will be greater than speed in dry air.
in the case of light waves it is the inverse, with increase in density its speed decreases

Answer 3

You are being very greedy! So many questions and that too typed so crampily! Pl. post separately.

OK, first question.

Which of the following is more elastic?

rubber is the right answer