Ninth Grade Science Projects (Page 27)

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

Heavy Metals and Aquatic Environments

Science Fair Project Idea

Scientific Method

You might know that lead can be toxic, and that you can get lead poisoning from eating or inhaling old paint dust. Lead is called a heavy metal, and there are other sources of heavy metals that can be toxic, too. Silver, copper, mercury, nickel, cadmium, arsenic, and chromium are all heavy metals that can be toxic in certain environments. In this experiment, find out if one common heavy metal, copper, can be toxic to an aquatic environment. Read more

Helicopter Liftoff: How Does the Speed of the Rotor Affect the Amount of Lift?

Science Fair Project Idea

Scientific Method

Helicopters are fascinating to watch. The spinning rotor blades on top of the helicopter generate lift, allowing it to take off vertically. They can land vertically, too, allowing them to set down in small spaces, such as hospital helipads or on a ship at sea. In this aerodynamics science fair project, you will fly a remote-controlled helicopter and measure how the rate of the rotor's rotation changes as the helicopter hovers and flies up or down. 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

Here Today, Gone Tomorrow: Saving Migratory Animals

Science Fair Project Idea

Scientific Method

Extinct might be a word you associate with animals that lived long ago, like the dinosaurs, but did you know that over 18,000 species are classified as "threatened" (susceptible to extinction) today? Scientists involved in wildlife conservation have a tough job; they are in charge of determining what needs to be done to prevent a species from becoming extinct. Habitat, food supply, and impacts of local human populations are just a few of the factors these scientists take into account. It is a… 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

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

Household Water Usage

Science Fair Project Idea

Scientific Method

How much water do you use? Conserving water can do more than save your parents' money, it can also save freshwater ecosystems, wetlands, and watersheds. Some companies are trying to help fix the problem by making low flow faucets and showerheads. How well do they work? How much water can you save? Go to the hardware store to buy a few of the water saving products. Compare the amount of water that you run over a period of time to determine how much water you can save. Which water saving… Read more

How Blue is Your Sports Drink?

Science Fair Project Idea

Scientific Method

Do you read the list of ingredients in foods and drinks before you buy them at the grocery store? If you do, you may have noticed that many of the items, especially colored drinks, contain dyes with names such as FD&C Blue 1, Red 40, or Yellow 5. But how much dye is needed to create all these colors? In this chemistry science project, you will build a simple spectrophotometer that is able to measure the concentration of colored chemicals in solutions. You will test your device by measuring… Read more

How Bright Is Your Glow Stick? Measure It!

Science Fair Project Idea

Scientific Method

Objects that glow in the dark hold a special place in the imagination of both children and adults. The lights go out at night, but these odd things refuse to disappear. Where does the light come from? Do they work in any climate? In this science fair project, you will make a very simple electronic device to measure the light given off by luminescent materials. The device will be used to study how temperature affects luminescence. Read more

Ninth Grade Science Projects (633 results)

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