A stone thrown into still water, creates a circular wave pattern moving radially outwards. If r is the distance measured from the centre of the pattern, the amplitude of the wave varies as

A stone thrown into still water, creates a circular wave pattern movin

1.	A stone thrown into still water, creates a circular wave pattern moving radially outwards. If r is the distance measured from the centre of the pattern, the amplitude of the wave varies as
Answer» `R ^(-(1)/(2))` `r ^(-1)` `r ^(-2)` `r ^(- (3)/(2))` Solution :For circular waves (propagating in `2-D` space i.e. on the surface) we have `I PROP (1)/(r )` But `I prop A ^(2) implies A ^(2) prop I implies A prop sqrtI` `THEREFORE A prop (I)/(sqrtr) implies A prop r ^(-1//2)`