[saman_Z]

is sp3 hybridisation also a factor apart from the lone pairs on oxygen atom..?

[macman104]

No, because oxygen is sp3 for both alcohols and ethers.

In all cases, most things can be considered by the following famous letters:  IRS.  Inductance, Resonance, and Sterics.  In this case, the I is responsible.  We can consider the following dipole-vector diagram (idea courtesy of azmanam).  We can consider the case of diethyl ether.  CH₃CH₂OCH₂CH₃:

You will see that the electron pairs have a net electron push into them, and thus have more negative charge to attract H⁺.

[nj_bartel]

The carbon, though more electronegative than hydrogen, has more electrons to shift toward the oxygen - the induction mentioned.

[saman_Z]

hey is it not because the lone pairs on 'O' atom are localised while in phenols are delocalised due to resonance!!!!!!!!!!!!!!! (though it can also be explained on  the basis of inductive effect) 

[macman104]

hey is it not because the lone pairs on 'O' atom are localised while in phenols are delocalised due to resonance!!!!!!!!!!!!!!! (though it can also be explained on  the basis of inductive effect) 

The question did not say phenols, it asked about alcohols (which I suppose phenols are).

But, yes, phenol is actually slightly acidic, because the resulting anion is so stabilized by the resonance, correct!

[Loyal]

hey is it not because the lone pairs on 'O' atom are localised while in phenols are delocalised due to resonance!!!!!!!!!!!!!!! (though it can also be explained on  the basis of inductive effect) 

In the case of Phenol I would think the resonance would be the primary factor.  You have a nice aromatic ring there to help stable your anion.

[Vidya]

In very simple words -oxygen of ethers is more rich in electrons because of inductive effect(electron repeling effect of two alkyl groups on it ).So it has more tendency to give its electron to positively charged hydrogen i.e. more readily to undergo protonation.

[Mitch]

I would argue that the inductive effect is more important in stabilizing the product, oxygen cation, than what has been stated by others in this thread, "[ethers] have more negative charge to attract H⁺".   

[nj_bartel]

Haven't thought of it that way.

[Mitch]

Haven't thought of it that way.

Then I'm doing my job.

[saman_Z]

either ways is right.
   due to inductive effect electron density around O atom increases and protonation is made easy....
      thank u all for your kind responses!!!