Riddle Definition and 152 Threads

Two days ago in my physics class, one of my friends asked me a question: "There are 2 identical circular coils with radius 'r', length 'l' and 'n' no. of turns placed with their axes lying on a straight line, and current is let to pass through them so that mutual induction is observed.What...

My mum told me this one, it's pretty cool :). The red car and the blue car are having a race. The red car, which has a top speed of 70mph has a 20 minute head start over the blue car, which has a top speed of 80mph. Assuming that top speeds are reached the very instant a car starts, and...

So I've run into Einstein's Riddle... The answer is "The German" - but we're not done. What about the fact that only 2% of the world population will be able to solve the riddle? Say if you only considering the population in the USA, I'm quite sure at least 20% of the population should be...

A friend of mine asked the following riddle. 2 mile stretch of road and you average 30MPH for the first mile, how fast do you need to travel for the 2nd mile to average 60 MPH over the entire trip. This would seem simple enough not taking into consideration time. Is it true that since the...

Today in physics lecture our physics teacher left us with a riddle. If you had an infinite grid of resistors say with 1 ohm of resistance set up between every node of the grid and then you connected a battery that supplies a current of one amp through across a single resistor, what would be...

ok, the story goes like this: a men was shot, one bullet killed him and the other missed him and got stuck into a heavy wooden chair (about 20Kg). the bullet made it 4cm into the chair, and the chair was pushed 6cm away by the 5 grams bullet (there were dragging marks on the wooden floor from...

Riddle game - Something for you scientists :) Hey guys! I found this online riddle game. I figured people on this forum might like it. You need to be a good thinker to solve this baby. Just enter transylvania and try to find an answer to the riddle you get by looking at the given picture...

A person enters a room with 5 doors. One of the doors will lead him to safety and the other 4 will lead him to hell where he will die. In the middle of the room, there are 5 stones lined up in a single file, numbered 1 to 5. These stones will either lie or tell the truth, but the stones have to...

On the piece of paper handed out in class please write a number between 0 and 100. The winner is the one who comes closest to 2/3rds of the average of numbers written by the students of the class. Question: What number should you write?

This one may take a while to get to the physics but is a good challenge for a mate with a sharp mind. My friends would like to know the answer and the physics behind it, so any answers would be appreciated. There was an OLD man out for a walk one afternoon and he decided to walk across a long...

Hacker riddle. I got past the signup problem, and I'm stuck on level 1. Me not being a hacker might have something to do with that. http://mod-x.co.uk

Lets assume that the old saying "nice guys always finish last" is true. A running race is held around the block with five people competing. Two nice guys are in the race. To finish the race, a runner must cross through a gate fit to hold only one person at a time. Who will finish last? Under...

Two planes take off at the same exact moment. They are flying across the Atlantic. One leaves New York and is flying to Paris at 500 miles per hour. The other leaves Paris and is flying to New York at only 450 miles per hour ( because of a strong head wind ). Which one will be closer to Paris...

Hi there I have a riddle here, i cannot solve. :cry: Please help me. :shy: If 4*12=6 and 8*8=1 what's 5*6? Thank you in advance.

You drive a car at a speed of 40 km/hr to a place and then 60 km/hr back... what is the average speed of the car. I feel really stupid for asking this but its really making me mad..

Pity Man need help... there is a MAN, he has a Goat, a Flower and a Lion. the man has to cross the river with his animals and the flower... how wud it b possible bcoz... 1) he can take one thing with him at a time. 2) he can't leave goat and flower togather as goat will eat it.. 2) he...

How can you figure out that you have not been programmed to be a Manchurian Candidate? How can you figure out that you have been hypnotized to be what you are? How can you figure out that you are not just some code in a computer, like in the movie The Matrix? How can you figure out that...

You might have heard this one, oh well, kinda easy. Once a man claimed that nobody could solve his riddle. It was, what is the answer. He gave them one hint-"the answer is everywhere" one person took a guess and got it right. What was the answer and why was it so hard? :biggrin:

This is not a logic puzzle, but just an old riddle I happen to like, called the Fisher's riddle. The ones we catch we throw away. The ones we don't catch we keep. What are they catching and not catching?

2+2=4 4+4=8 142+468=621 3762+8271=? driving me crazy

there is a three story building, with a total of 12 people in it. it rained. and the roof leaked. the people from the third floor asked the second floor people if they could go down to the second floor. the second floor people then said they could only acomodate (on the second floor) the same...

Hi, I've a riddle that I can't solve. I hope someone can help me in it. Here is it: If we have a number and add the digits of that number, then subtract the summation we got from the original number, why is the result always multiples of the base system minus 1. Here is an example...

Here's an easy riddle: You are in a room with 3 switches. The room is adjacent to another in which there are 3 lightbulbs. Each of the lightbulbs is connected to a switch in your room. You cannot see into the other room. You may manipulate the switches in any way you like, and you may go to...

Einstein wrote this riddle last century and said that 98% of the world’s population would not be able to solve it. Are you a part of that 98%? * There are 5 houses that are each a different colour. * There is a person of a different nationality in each house. * The 5 owners drink a...

Here is a riddle that 80% of the students at Princeton University could not solve but 90% of all first graders asked, replied with the answer in less than 5 minutes. Q: What is greater than God, more evil than the Devil, rich people need it, the poor people have it, and if you eat it you...

I just received the following riddle and am trying to figure it out While wearing Amethyst colored glasses, John Neun gave George Burns the following riddle: "Look closely and you will see something between Pi, You and Me. What do you think?

here is one of my favorites Ok, Imagine you are on a small island. Now, At this moment, lava is cascading down all sides of a volcano. You can not stay on this island and survive. Now, in the water surrounding this island their is a complete ring of people in boats with guns, who have to...

Okay, I'm sure you've heard some sort of variation of this, but it's still pretty good... You're on an island and desperately need to get off alive. There are 2 caves in front of you. One cave tunnels under the ocean somehow and leads to safety, and the other cave leads to certain death...

Help me solve this maths riddle! John forgot to bring his house keys with him,so he must use secret numbers to open his house door.But he reasiled that he totally forgot the numbers,despite of that,he still insisted using the secret numbers. When he got there, he came to a combination lock on...

I LOVE riddles! A man is to be put to death for murder. The exicutioner says "You can say one thing. If i find it is a lye then i shall drown you. if i find it true i shall hang you." What can the criminal say to be spared?

Four away from the brightest, five away from the dimmest, Turning and Turning around one sphere, Four away from the end, a lot of ways from the beginning, If you were to stand, you are to place on here I think this is related to astronomy :rolleyes: , but I'm not too sure. I hope...

Once you have worked it out, how do you tell people?

here is a little riddle http://www.quantumninja.com/toe/modules.php?name=News&file=article&sid=4&mode=&order=0&thold=0 it is on my new site www.quantumninja.com/toe

There is fierce fighting between two countries, that we will be referred to as Country Bob, and Country Joe. To solve the problem the UN gets the leaders of Bob and Joe decide to sign a peace agreement to end the violence, the problem is that neither leader wishes to sign it first. To solve the...

Math related riddle! Three people check into a hotel. They pay $30 to the manager and go to their room. The manager suddenly remembers that the room rate is $25 and gives $5 to the bellboy to return to the people. On the way to the room the bellboy reasons that $5 would be difficult to share...

Give yourself a minute or two to solve this : You have 2 boxes and 20 balls, 10 black and 10 white. How would you distribute the balls in the boxes (any number in each box so long as the total is 20) to maximize the odds of picking 2 whites on a random selection of 1 ball from each box ...

Here's a classic riddle (whose statement I am totally butchering, but that's ok!): "A man is carrying a canister of liquid which he claims to be a universal solvent. How do you know he's lying?" This text here is a bit of filler warning you that I'm going to spill the answer to this riddle...

What is 1+1? the answer begins with F. Is not Function, not Fraction... Don't know what the answer is. It is suppose to be a riddle.

Hello, I have been given a question which consists of a riddle in a mono-alphabetic code - it is a question that is part of our crytography section. Now I have decoded the riddle. But I am not sure if I have solved the riddle. Here is the riddle I decoded: Now I didn't have to try...

Hi guys, Attached is a diagram design in principle i drew some time ago It's pretty self explanitory I was wondering if some one can tell my why it is invalid and doesn't work.

Above the photosphere is the chromosphere and above that, the corona. Sometimes our sun sends out big, bright fire loops reaching high up into the corona. What is this called?

Can you make another sentence with a similar, though opposite, meaning of the one below by rearranging the words? When large humans scare tiny animals, they are such beasts that they let loose a roar.

With a blank ruler (without marks) of exactly 36 cm you can only measure 36 cm. Now you are allowed to set 8 marks so that you can read off all full centimeter values from 1 to 36 cm directly from the ruler. Where must these 8 marks be?

Way, dog, ground, handed? see brain teaser #23

see: https://www.physicsforums.com/showthread.php?threadid=4134 Sun, Side, Rug

I give you three words, and you must type in the single word that can be added to each to make three new words. Example: fish, board, dust. Answer: star (starfish, starboard, stardust) Ray, Hole, Ion

A D M I T C A P E R R O B E S T A L O N WORKED EXAMPLE (1)The choice of the first letter of the mystery word is either a C, R, A or T as these are the first letters of the given words. (Choose C). (2)The second letter of the mystery word is either and A, O or D (A is...

It's more powerful than God. It's more evil than the devil. The poor have it. The rich need it. If you eat it, you'll die. What am I?

1.A logician is traveling in a country where the inhabitants are of two types. Members of one group always tell the truth, the others lie. The traveler comes to the fork in a road and has to ask a native bystander which branch he should take to reach the village. He has no way of telling...

This has an answer, but it makes a nice puzzle for the mathematically inclined so I'm presenting it as a riddle. You have a hypersphere of n dimension and you want a function which describes a non-geodesic line which never crosses itself in the space of the sphere. Questions: What is the...