Moore's law and Clock Speed

Problem Detail: 

This figure says according to moore's law number of transistors doubles about two years. but clock speed, power flattening after given stage. can anyone describe the reasons this flattening in clock-speed. Why can't we increase the clock speed more and more?

Asked By : Canon

Answered By : lPlant

Here is a link to a similar discussion in another stack exchange where the causes are explained.

Best Answer from StackOverflow

Question Source : http://cs.stackexchange.com/questions/27875