Ever notice people wearing headsets to keep out noise? Check out the workers on the tarmac of airports, or gardeners with their leaf blowers, or road workers breaking up blacktop with a pneumatic drill. They wear these headsets to protect their ears from damage caused by persistent loud noise. Loudness is measured in decibels, dB for short. Complete silence is 0 dB, a whisper is 10 dB, normal conversation is 60 dB or about 10,000 times louder than a whisper. A lawnmower is 90 dB, about 1,000 times louder than a conversation and a jet engine is 120 dB about 1,000,000 times louder than a conversation. Anything over 85 dB does damage to our ears. That’s because sound traveling through air is a force beating against delicate eardrums. Yes, rock concerts damage ears. Performing musicians often have tiny earpieces in their ears. This way the sound engineers can send them the sounds of their own voices or instruments, so that they can hear themselves over the other musicians. Those pieces are not for protection. So the dB level of rock concerts can affect those musicians’ hearing. There is even a name for it: Noise Induced Hearing Loss or NIHL. Rock musicians are the top profession to suffer NIHL later in life. But there is a new threat to hearing loss—the earbuds people use to listen to music from their electronic devices. They are fine if you keep the volume down. But if you’re hooked on loudness that invades all your senses so that you can’t “hear yourself think” and you listen for several hours a day, you’ll pay the price down the road. Your ability to hear high tones is the first to go. Here’s a quick and easy hearing test you can use on yourself and your family: Turn on the TV and hit the “mute” button or turn the volume all the way down. Lean over the back of the set and listen for a very soft, high-pitched whine. If you can hear it, you are listening to the highest sound the human ear can hear. (Dogs, of course, can hear much higher sounds, hence the dog whistle, which people can’t hear but dogs can.) Walk away from the set to find the distance when you can no longer hear it. Do the same test with your parents. Bet your hearing is better than theirs. Try listening to some old-fashioned, melodic, soft popular music that came before rock and roll. You just might like it.  Listening to her own soft music, or just blocking out your loud music? Either way, her hearing is better than yours. Photo by Alexandra Siy  From School Library Journal-- "Fun!" comes through loud and clear in this energetic exploration of hearing and auditory perception. Cobb gets the anatomy lesson out of the way, then moves on to a series of simple activities to help kids experiment with their own sense of hearing. Students investigate sound conduction, perception of pitch, echolocation, and range of hearing by doing such things as sticking fingers in their ears while they talk." Available for download at the i-Tunes store -- click here. Vicki Cobb is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more. MLA 8 Citation Cobb, Vicki. "Banging on the Ear Drum." Nonfiction Minute, iNK Think Tank, 30 Apr. 2018, www.nonfictionminute.org/the-nonfiction-minute/Banging-on-the-Ear-Drum. 
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Earth has a problem. The sun creates hot spots over land, in the air and in the water. That’s why there are winds, weather, and currents in the ocean as Earth tries to even out the heat, moving warmer masses of air and water to cooler areas. During hurricane season ( from June 1-November 30), only 10 or 11 of the 80 tropical disturbances off the west coast of Africa (where most of our hurricanes originate) become large enough storms to be given a name. Only two or three of them hit the United States. They are not frequent but they are massive wind storms that can destroy life and property. Do they do anything good at all? As far as the Earth is concerned, these largest of all storms are a safety valve to rapidly move heat that has been accumulating in the oceans up to the stratosphere (from 7 to 31 miles above the Earth’s surface). From there it will be transported through the air to over the North Pole. It’s the way Earth stops a fever. Once a hurricane forms, it must have an ocean surface that is at least 80°F to keep moving and to grow. Under the storm, huge amounts of warm water become water vapor. Warm moist air rapidly rises through the spinning winds of the hurricane, up to the stratosphere. When moist air reaches the frigid (-70°F) stratosphere the water vapor quickly condenses to liquid water (rain) releasing its heat. This heat makes surrounding air molecules move faster forming winds. How do hurricanes cool off the oceans? How do they move the heat? Here’s a clue: Wet your finger and wave it in the air. How does it feel? Pretty cool, I bet! That’s because the heat from your finger changes liquid water into water vapor (a gas) as your finger dries. Water vapor molecules store this extra heat. They rise because they are lighter than other air molecules. So, a hurricane is a heat engine that moves water vapor from the ocean’s surface high enough to condense back into liquid water and release heat safely to the stratosphere forming rivers of wind that move it to the poles. Scientists predict that global warming will increase the number and the power of the hurricanes as the ocean surfaces become increasingly warmer during our summers.  This diagram of the anatomy of a hurricane shows the direction of the winds. The blue represents cold air descending while the pink shows warm moist air rising. The outflow surface clouds form as water condenses into a "table-top" cloud, releasing heat that becomes wind. Kelvinsong via Wikimedia  Hurricane Isabel (2003) as seen from orbit during Expedition 7 of the International Space Station. The eye, eyewall, and surrounding rainbands, all characteristics of hurricanes, are clearly visible in this view from space. Image courtesy of Mike Trenchard, Earth Sciences & Image Analysis Laboratory, NASA Johnson Space Center  Vicki Cobb's How Could We Harness a Hurricane? offers questions and provides new points of view that may just change peoples' thinking by showing young readers the work scientists and engineers are doing to avoid future disasters. The book includes hands-on experiments that make science fun, be it at home or in the classroom. Here's a link to the book' s Trailer. How Could We Harness a Hurricane was named a 2018 Best STEM Book K-12 by the National Science Teachers Association and the Children's Book Council. Vicki is a member of iNK's Authors on Call so you can invite her to your classroom via iNK's videoconferening Zoom Room. Click here to find out more: MLA 8 Citation Cobb, Vicki. "Earth's Emergency Heat Valve: The Hurricane." Nonfiction Minute, iNK Think Tank, 24 Apr. 2018, www.nonfictionminute.org/ the-nonfiction-minute/Earths-Emergency-Heat-Valve-The-Hurricane.  
No one wants to mess with someone who is super strong! Even if you’re undersized, especially if you’re undersized, you’ve got to try the two tricks in this Minute .
Here’s the first challenge: Bet another person can’t remove your hand from the top of your head. The challenge-taker must try to remove your hand according to your rules. Otherwise, it’s cheating. Sit on the floor. Place your hand with your fingers spread apart firmly on the top of your head. Have your friend grasp your lower arm next to your elbow. Now let him/her pull upward, trying to lift your hand from the top of your head. Chances are excellent that you’ll be lifted off the ground before your palm parts from its perch. Why is this so? If you’ve studied simple machines you may have learned about a mechanical advantage. That’s how a simple machine such as a lever can multiply your strength or speed. In this case, you’re putting your friend at a mechanical disadvantage. Your arm is a lever. In order to move your hand from the top of your head, you need an upward force near your hand. If that force is delivered as far away from your hand as possible, it loses its power. It’s easy to remove your hand if you deliver an upward force near your wrist. But at your elbow? No way! Got it? Here’s another trick with the secret sauce of physics. Bet you can keep ten people from shoving you into a wall. Place your hands against a wall with your fingers spread and your arms outstretched. Have ten people line up behind you, hands on the shoulders of the person in front of them. At the count of three, have everyone push on the person in front of them as hard as they can. I mean, really lean in. You, hero of the day, can hold them all off and not bend your elbows. Why? Actually, each person absorbs the force of the person behind them so that you are not experiencing the cumulative force of ten people, only the force of the person directly behind you. So pick someone smaller than you to be that first person. If you’re not super strong, you can still be super smart. If you don’t want to try this yourself, look at my videos of other people doing the challenges. Maybe you’ll change your mind. 
If you like these bets, check out Vicki Cobb’s new release of We Dare You! You might want to join her We Dare You! National Video Project and make more videos yourself from her book. Learn more about it here.
Vicki Cobb is a member of iNK’s Authors on Call. You can invite her to your class through the magic of videoconferencing. Learn more about it here.
MLA 8 Citation
Cobb, Vicki. "How to Make Your Friends Think You're Super Strong." Nonfiction Minute, iNK Think Tank, 23 Mar. 2018, www.nonfictionminute.org/ the-nonfiction-minute/How-to-Make-Your-Friends-Think-Youre-Super-Strong. 
 You can’t play tennis unless you know where the ball will be after it bounces. You can’t pass a basketball unless you understand how to angle a bounce so that it goes where you want it to go. As long as the court surface is smooth and flat, a ball’s bounce is very predictable. Its path depends on gravity and on the strength and direction of the force that sets the ball in motion. Thanks to high speed photography we can get a closer look at a bouncing ball. This is a multiple exposure photograph of a bouncing ball. It was taken in complete darkness with the camera shutter open while a high-speed flashing light, called a stroboscope or strobe, flashed 30 times a second. Each flash produced an image. Here’s what you can learn from this photo: The ball is moving fastest where the images are farthest apart and slowest where they are closest together. When the ball is falling, it speeds up. After it bounces and moves opposite the pull of gravity, it slows down at exactly the same rate as it sped up when it was falling until it stops for an instant and starts falling again. Each time it collides with the ground, some energy is lost. That’s why each bounce loses altitude. If the bounce were perfect, no energy would be lost, every bounce would be as high as the last and the ball would bounce forever. A strobe also captures the split second when a tennis ball is struck by a racket. The collision flattens the ball, and stretches the strings and distorts the frame of the racket, all in .005 seconds. If these objects kept their distorted shapes, most of the force of the collision would be absorbed. But they are elastic—they restore themselves to their original shapes after they collide. This restoring force is transferred to the ball to change its direction and help add to the speed of the athlete’s swing. The fastest serve leaves a racket at 130 miles an hour. In a rally, a ball-racket collision changes direction of the ball so it is not as fast as a serve, maybe 70 miles per hour. Since the distance between images made by a strobe tells how fast an object is moving, strobes are part of the instruments used to measure the speed of balls from a tennis racket and a baseball pitcher.  Photo credit: C. E. Miller, MIT In this MIT YouTube, a ball is dropped in front of a meter stick and lit by a strobe light. A long exposure photograph captures the position of the ball at each evenly spaced flash of light. The acceleration of the ball can then be measured from the photo.  Would you believe that you could throw an egg across the room without breaking it? Burn a candle underwater? Vicki Cobb's We Dare You! is a gigantic collection of irresistible, easy-to-perform science experiments, tricks, bets, and games kids can do at home with everyday household objects. Thanks to the principles of gravity, mechanics, fluids, logic, geometry, energy, and perception, kids will find countless hours of fun with the selections included in this book. If you would like to make a We Dare You Video, click here. Vicki Cobb is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more. MLA 8 Citation Cobb, Vicki. "A Bouncing Ball Like You've Never Seen." Nonfiction Minute, iNK Think Tank, 5 Feb. 2018, www.nonfictionminute.org/the-nonfiction-minute/ a-bouncing-ball-like-you've-never-seen.  
In October, 1891, 23-year-old Manya Sklowdowska arrived in Paris to attend the Sorbonne, France’s great university. She had saved money, working as a governess to get there. She was determined to make the most of her studies in science and math. Right away she was noticed partly because she was Polish, although she had changed her first name to a French version, Marie, to fit in better. She always sat in the front row of all her classes because her French was not yet fluent and she didn’t want to miss anything. She also was one of only a few female students. In a university full of smart people, she worked hard to excel. She ultimately finished first in her class and went on to make major scientific discoveries. What made Marie so single-minded and determined? Behind it all was a great love for science, a love she shared with her husband, Pierre Curie, whom she met in 1894. At that time, science was uncovering unimaginable truths in chemistry and physics. New discoveries were being made at a breath-taking pace. Science was like a game and it attracted many players. Why? 1. There was a Nobel Prize for winners, those who discovered a big idea about the natural world. There was only one nature to discover but people came at it from many directions. 2. It was collaborative—scientists shared their discoveries by publishing papers. 3. It was competitive—the papers described procedures so that scientists could check each other’s work. It kept everyone honest. The best work got the most attention. 4. The discoveries could be applied to solve problems for people. X-rays, light bulbs, phonographs, photographs, movies, and telephones would not have been possible without science. 5. The biggest prize was the idea of the atom and its structure. Many scientists contributed to modern atomic theory, including Marie. Marie Curie won the Nobel Prize twice for her work. At a time when women didn't even have the right to vote, she was a working mother of two daughters, a single mother after she was widowed in 1906, the founder of the Radium Institute for research and she brought the x-ray to the battlefield in WWI. She believed that science could save the world, that scientific discoveries belonged to everyone. And she refused to benefit financially from her discoveries. She lived by the highest principles of honesty and integrity. She was a true champion of the science game.
 DK Biography: Marie Curie tells the story of the discoverer of radium, from her childhood in Warsaw, to her experiments with radioactivity in Paris, to her recognition as one of the preeminent scientists of her time. Filled with archival photographs and amazing fact boxes, this biography paints Marie Curie as the brave and brilliant scientist that she was. Vicki Cobb is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more. MLA 8 Citation Cobb, Vicki. "Marie Curie: An Elite Player in the Science Game." Nonfiction Minute`, iNK Think Tank, 30 Jan. 2018, www.nonfictionminute.org/ the-nonfiction-minute/Marie Curie-An-Elite-Player-in-the-Science-Game.  |
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