Riddles > Science Riddles

Black When You Buy It, Red When You Use It

These science riddles will have you scratching your head.

Black When You Buy It, Red When You Use It
Riddle:
What is black when you buy it, red when you use it, and gray when you throw it away?
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It Is Energy and Motion...
Riddle:
It is energy and motion, it can fly across the ocean. It can listen and even speak, it can see and even seek. It eats neither fruit nor gruel, it eats energy and fuel. Better say: It doesn't eat; It is transformed into heat. What is it?
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What Force of Nature Am I?
Riddle:
The shape of my form will waver and bend By the things I’m destroying and those I will rend. My color changes from bright red to blue, The power I’m using will dictate my hue. What am I?
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The Man and the Bear
Riddle:
A man is sitting in a small house with 4 walls. All of the walls are facing south. There is a bear lurking near the house. What color is the bear?
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The Cat That Crossed a River
Riddle:
A boy stood on one side of a river, and his cat was on the other side. When the boy called his cat, it crosses the river right away. Moreover, the cat's fur remained completely dry, and it didn't use a boat, bridge, or any other manmade vessel or structure to cross the bridge. How did the cat do it?
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The Taxi and the Aardvark
Riddle:
What did the aardvark ask the taxi driver?
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How Many Animals Are Going to the River?
Riddle:
1 duck saw 4 elephants as it was going toward the river. Every elephant noticed 2 monkeys going to the river. Every monkey was carrying 1 dove in its paws. How many animals are going to the river?
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Animals on the Bed
Riddle:
You enter a room and notice a bed. There are 3 dogs, 2 cats, 1 goat, 4 crows, and a goose on the bed. In addition, 3 sparrows are flying around the bed. How many LEGS are there on the floor?
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Son of a Chemist
Riddle:
I am the son of a chemist and a mathematician. People call me iron 59. What is my name?
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Canaries into Space
Riddle:
NASA was considering sending canaries into space to study them under zero gravity. The project was scrapped when someone realized that in spite of having sufficient water supplies, they could die of dehydration within a few hours. Why?
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A Pregnant Lady
Riddle:
A pregnant lady named her children: Dominique, Regis, Michelle, Fawn, Sophie and Lara. What will she name her next child? Jessica, Katie, Abby or Tilly?
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Hole in the Night
Riddle:
I am the hole in the night, the ever-watchful eye. I return in a cycle, to enlighten the sky. Who am I?
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Drink and I Die
Riddle:
Feed me and I live, give me drink and I die. What am I?
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Sands of Time
Riddle:
The prisoner was locked up in a room with a dirt floor. The room has one window, which is high up above the prisoner's height. The prisoner had a shovel, but he had only 2 days to get out, and digging would take him more than 5. How would he escape?
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The Pole of Death
Riddle:
Dr. Miller was staying with his cousin, Alfred, in Alfred’s lakeside cabin. They were setting up Alfred’s will. Since Dr. Miller was Alfred’s closest living relative, much of Alfred’s estate was being left to him. One day, Alfred went to Dr. Miller very upset. “Doctor,” he began, “I have just found out that an old enemy is out to get me. He is coming very soon. Where will I go? Where can I hide? If he finds me, he will surely kill me. I do not have time to leave this cabin and hide in the woods.” Dr. Miller thought for a moment, and then grabbed a 5′ long bamboo fishing pole, with a diameter the size of a quarter. “Alfred, follow me out to the lake. This lake is 4′ deep. If you lie on the bottom of the lake and breathe through this pole, your enemy will never find you. I will be in the bulrushes with a shotgun, and I will shoot him when he comes. I will swim down to find you when he is gone.” Alfred thought that was a great idea and went down to the lake with the bamboo pole in his mouth. A few hours later, a ranger passed by. He found Alfred’s body. Dr. Miller told the police of the circumstance, and that Alfred had probably panicked, and died. Police arrested Dr. Miller on the charge of murdering Alfred. Why?
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Only One Color
Riddle:
Only one color, 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?
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Medical Condition to Make You Run
Riddle:
What medical condition makes you run faster?
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Physicists At Sporting Events
Riddle:
What do physicists enjoy doing the most at sporting events?
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The Soccer Ball Quits
Riddle:
Why did the soccer ball quit the team?
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I Am a Ball That Can Be Rolled
Riddle:
I am a ball that can be rolled but never bounced or thrown. What am I?
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I Am Present in Marshes
Riddle:
I am present in marshes And also in the rumen of cattle To stop global warming I do very little. What am I?
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When Liquid Splashes Me, None Seeps Through
Riddle:
When liquid splashes me, none seeps through. When I am moved a lot, liquid I spew. When I am hit, color I change. And color, I come in quite a range. What I cover is very complex, and I am very easy to flex. What am I?
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I'm Unique in One Way
Riddle:
I'm unique in one way but you can find two of me in your daily drink. What am I?
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Femur and Patella
Riddle:
What did the femur say to the patella?
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I May Not Be Gold But I Make Gold Look More Beautiful
Riddle:
I may not be gold but I make gold look more beautiful. I help you fly and even though I'm not popular, my prices run high. What am I?
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Shiny Like Silver, Denser Than Lead
Riddle:
Shiny like silver, denser than lead, pricier than gold, could stop a bullet if I wanted to. What am I?
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Tree That Can Fit Into Your Hand
Riddle:
What kind of tree can fit into your hand?
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Ben Franklin
Riddle:
How did Ben Franklin feel after discovering electricity?
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Anyone Can Hold Me, Even Without Their Hands
Riddle:
Anyone can hold me, even without their hands, yet no one can do it for long. What am I?
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Element That’s Derived from a Norse God
Riddle:
What element is derived from a Norse god?
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