The Floating Cork

If a cork is placed into a glass of water, it will almost always drift to the side of the glass. There is one simple way, however, to get the cork to float in the center of the glass. What is it?

Water, the glass, and the cork are all that is required.

The reason that a cork drifts to the side of a glass is that it floats to the highest point. Since water “clings” to the glass, the highest point is around the edge of the water. To get the cork to float in the middle of the glass, all you have to do is fill the glass as much as possible. The water will form a convex shape above the glass, with the highest point at its center. This is where the cork will settle.

Posted in Brain Teasers

A Dog Running in the Forest

How far can a dog run into the forest?

Halfway. After that it will be running out of the forest.

Posted in Brain Teasers

I Wear You Down

I wear you down, yet you will mourn me once I fly.
You can kill me, but I will never die.

Time.

(found in The Copper Gauntlet by Holly Black and Cassandra Clare)

Posted in Riddles

Money For Answers

A dad offered to pay his son $5 for every correct answer on his math test. His son said he would pay his Dad $8 for every incorrect answer. There were 26 questions on the test and no money was exchanged.

How did this happen?

The son got 16 questions correct and missed 10. This means he owed his Dad 10 * $8 = $80, but his Dad owed him 16 * $5 = $80, so it was a wash.
Two math equations to solve it are x + y = 26 and 5x = 8y.

Posted in Brain Teasers

Cats Catching Mice

5 cats can catch 5 mice in 5 minutes. How many cats does it take to catch 100 mice in 100 minutes?

5 cats. The same five could keep catching 5 mice every 5 minutes for 100 minutes.

Posted in Brain Teasers

Two in a Corner

Two in a corner,
One in a room,
Zero in a house, but one in a shelter.

What am I?

The letter “r”.

Posted in Riddles

First One, Then I Seem None

First I am one, then I seem none,
In death I birth new life.
What’s raised exceeds me,
For on bent knee,
I add to a world that’s rife.

What am I?

A seed. One seed turns into a plant or tree and seemingly disappears. When a plant dies, the seeds can be harvested to create new plants. From a single seed, hundreds more are created, vastly exceeding the original. Gardeners care for plants on bent knee and each new plant helps make the air fresher.

Posted in Riddles

Six Glasses In a Row

There are six glasses in a row. The first three are full of water, and the next three are empty. By moving only one glass how can you make them alternate between full and empty?

Pour the water from the 2nd glass into the 5th glass.

Posted in Brain Teasers

$63 Exactly

A man owed his friend $63 and repaid him the exact amount in cash without using coins or $1 bills (no online transfers, checks, credit cards or any other tricks) and without requiring change. How did he do it?

A $50 bill, a $5 bill and four $2 bills.

Posted in Brain Teasers

Poor Sheep

A farmer had 17 sheep. All but 9 died. How many live sheep does he have left?

9. If all but 9 died, there are 9 remaining live sheep.

Posted in Brain Teasers