What work can one never finish?

Why 1729 is a magic number? Answer Logically.

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

This puzzle is for Harry Potter fans. Do you know why Tom Riddle is called Lord Voldemort?

Can you find a five letter word that is left with only two letters if one is removed?

Be active and find the killer in the picture Riddle below.

What does below chemistry rebus means?

Only one colour, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

My first is in chocolate but not in ham. My second is in cake and also in jam. My third at tea time is easily found. Altogether, this is a friend who is often around. What is it?

what does the below math rebus puzzle mean?