Projects, Lessons, Activities (Page 162)

Heart Rate Recovery Times

Science Fair Project Idea

Scientific Method

Over an average lifetime, the human heart beats more than 2.5 billion times, supplying blood to the entire body. When a person exercises, the heart has to work harder than usual. Have you ever wondered how quickly your heart beats when you exercise, or how long it takes to recover back to its normal rate after you are done exercising? Is the heart rate recovery time faster for people who get regular exercise compared to people who do not? Try out this science project to find out! Read more

Helmholtz Resonance and Musical Instruments

Science Fair Project Idea

Scientific Method

Helmholtz resonance, or air cavity resonance, refers to the resonance of air in a container with a small opening, like a plastic bottle or the devices shown in Figure 1. The resonant frequency of the air depends on the volume of the air in the container and the geometry of the opening (its length and cross-sectional area). The Helmholtz frequency is not the same as the natural frequency of an air column in a cylinder, where the opening is the same size and shape as the rest of the cylinder. … Read more

Help! What File Format Should I Use to Save My Favorite Photo?

Science Fair Project Idea

Scientific Method

Jpeg, bmp, gif, tiff ... do these just look like words that you and your friends might make up for your own secret language? They are actually just a few of the file formats (which means "types") that you can use to save your favorite photo on your computer. But does it matter which one you use? Try this simple science fair project to find out and you'll never choose the wrong one again! Read more

Hey, Do You C My Potatoes? Determining Vitamin C Amounts in Cooked Potatoes

Science Fair Project Idea

Scientific Method

As you know, vegetables not only taste good, but they are good for you. Many vegetables are a great source of vitamin C. Vitamin C is a water-soluble antioxidant that plays an important role in protecting the body from infection and disease. Humans do not make vitamin C on their own, so we must get it from dietary sources. Potatoes, like the ones shown in Figure 1, below, are one good source of vitamin C. Does cooking them affect how much vitamin C they have? In other words, if you boil a… Read more

Hey Gear Heads! The Physics of Bicycle Gear Ratios

Science Fair Project Idea

Scientific Method

If you have a multi-speed bike, you know that you can make it easier or harder to pedal just by shifting gears. Ever wonder how that works? You can investigate this a number of ways. A basic approach is to use a selection of spools of thread (with different diameters), a board with two nails, and a rubber band. Place a spool over each nail, and put the rubber band over them. Mark the 12:00 position on each spool so that you can count revolutions. Turn one spool through a full circle and… Read more

Hey, There's Corn in My Candy!

Science Fair Project Idea

Scientific Method

If you browse through a candy cookbook, you might notice that many of the recipes call for corn syrup in addition to sugar. Both sugar and corn syrup are sweet, so why do you need corn syrup if you already have sugar? In candy making, corn syrup is known as an interfering agent. But what does this mean and how does it work? You can find out for yourself by making two batches of rock candy, one with corn syrup and one without. For example, you could alter the science project When Science is… Read more

Hit Boxes: How Size Affects Score

Science Fair Project Idea

Engineering Design Process

Video games come in many varieties: aim-and-shoot games, city-building games, racing games... the list goes on. In many, you get points for colliding with or hitting something. In this computer and video games project, you will learn about how hit boxes are used to detect collisions and you will determine if the size and placement of a hit box affects the score in the game. Read more

Holding Power of Nails

Science Fair Project Idea

Scientific Method

How strongly do different types of nails hold in wood? Try different diameters of nails, and try pounding them to different depths. To gauge the holding strength, measure how difficult it is to remove the nail. Can you pull it out with a pair of pliers? Can you remove it with the hammer claw? Do you have to push only a little bit, moderately hard, or as hard as you can? Do you need a crowbar? What happens if you pre-drill holes for the nails, using drill bits that are different… Read more

Honesty: How Prevalent Is It?

Science Fair Project Idea

Scientific Method

How trusting are you? Do you think people are basically honest, or do you think people are usually honest only when they think someone is watching? This project explores how well the honor system works for a bake sale-type charity donation. Find out if your hunch is correct. Read more

Hot Pot: Choosing the Right Pot in Which to Cook Your Meals

Science Fair Project Idea

Scientific Method

What is cooking? Cooking is applying heat to food in order to help make it taste good. But the decision to cook your food doesn't end there. Do you want to cook it at a low temperature for a long time or do you want to apply high heat and cook or sear it right away? You might think that a pot is just something in which to cook your food, but it is also a cooking tool. Pots and pans are made from different kinds of materials, such as aluminum, stainless steel, iron, and ceramics. Each of these… Read more

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