Logic Riddles

Question: A teacher decides to give a pop quiz one day but all of her students refuse to take the quiz thinking that the teacher will call off the quiz. She can give only one of these students a detention for skipping the quiz. All of the students know each other's names and if a student knows he/she is getting a detention they take the quiz.

How can she threaten her students with the single detention so they all take the quiz?

Question: You have 7 tennis balls that are all identical but one of them is slightly lighter than the others.

Using a balance scale and only two separate weightings, how can you find the light tennis ball?

Question: A king is on a cross-sea voyage and as soon as they get off of their boats he spots the most beautiful elephant he has ever seen. He decides to take it home, but first, he wants to know its weight.

The largest scale they brought only goes up to 50 pounds. The king demands that his smartest scholar must come up with a solution or pay the consequences. After several days he finally comes up with an answer.

Question: What goes around comes around?

Question: Surrounded by life , yet life is its biggest enemy. But without life there is no need for it to exist. What is it?