How many sides does a circle have?

Fate has decided that you will only be pleased to meet me when you need me

Maybe that is why, when I am working, I start working

However annoying I may be to the regulars, the little ones are always inspired

I will always be waiting if you try to reach me

How many of you can guess my name, let me see

If you say my name, I will no longer exist. What am I?

I have a clock(12-hour format) and both the needles of the clock overlap at 12:00.
After how much time, they will overlap again?

What has to be broken before you can use it?

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?

I have an eye but still cannot see.

Who am I?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

What demands an answer, but asks no questions

Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?