What is a metal? A metal is any material that readily loses its outer shell electrons, can be polished to be highly reflective of light, is opaque, conducts heat, conducts electricity, is ductile, and malleable. The bond between the atoms in the molecules cause all of these properties and are what makes a material a […]
#910 What is a metal? Read More »
Henrietta Lacks developed cervical cancer and the cells taken from a tumor biopsy have formed the HeLa cell line, named after her. Ms. Lacks didn’t know that her cells had been taken and she died in October 1951, before the significance of her cells was known. She was only 31 years old. She did not
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Why does dry ice fog sink? The gas from dry ice is more dense than air and therefore it sinks. Dry ice is solid carbon dioxide. It is called dry ice because when it melts it turns into a gas rather than a liquid. Regular ice would be wet ice because when it melts it
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During his career, Maurice Hilleman developed over 40 vaccinations. It is thought that his vaccinations save over 8 million lives every year. However, he was not interested in making a name for himself, only that his vaccines helped people. For this reason, despite having received his vaccines, very few people have ever heard of him.
#859 Maurice Hilleman – microbiologist specializing in vaccinology. Read More »
What is a gluon? It is a massless subatomic particle that carries the force that binds quarks together, known as the strong force. There are four forces that affect everything in the universe. These are gravity, the electromagnetic force, the weak force, and the strong force. They are known as the four fundamental forces. Gravity
#847 What is a gluon? Read More »
What color is the sea? It is technically blue, but that depends on the depth and what particles are in the water. The sky is blue because the blue light wavelengths are scattered by molecules in the air. This is not why the ocean is blue. Generally the sea is blue because water absorbs red
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How do noise cancelling headphones work? They play the sound from around you, but reversed, which cancels out the noise. Sound is a pressure wave that is created by an energy source that makes the molecules of the medium it is travelling through vibrate. Sound can travel through any medium and it travels through some
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Do antibiotics kill all of the bacteria in the body? Yes, they do. Antibiotics kill bacteria in the body. They do not work on viruses. We use bacteria when we have an infection and they can be very effective. An infection is caused when we have a wound and bacteria get inside. This is very
#808 Do antibiotics kill all of the bacteria in the body? Read More »
Why are clouds white? Because the water particles in the clouds scatter light equally. When light comes out of the sun, it is white. That is to say, it emits all of the colors of the color spectrum. The sun emits light as radiation and it emits radiation across almost all of the electromagnetic spectrum,
#805 Why are clouds white? Read More »
Why does a cracked whip make a sound? One portion of the whip moves faster than the speed of sound, creating a sonic boom. A sonic boom is created by anything that goes faster than the speed of sound, which is 343 m/s in air. Air behaves in the same way as a fluid, so
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