What has to be broken before you can use it?

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

I am a five-letter word and comprises two different vowels and three same consonants. I am so strong that I can spoil your entire work.

Can you find out who am I?

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?

In four steps you need to move the word 'cold' From 'warm' by replacing one alphabet at a time such that every word formed at each step is acceptable in English Dictionary.

The Puzzle: A girl, a boy, and a dog start walking down a road.

They start at the same time, from the same point, in the same direction.

The boy walks at 5 km/h, the girl at 6 km/h.

The dog runs from boy to girl and back again with a constant speed of 10 km/h. The dog does not slow down on the turn.
How far does the dog travel in 1 hour?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?

If an electric train is travelling south, then which way is the smoke going?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

What have one eye but still cannot see?