Background Video
Pressure is the ability to apply force to an area and have the force be distributed. Oobleck is such a great experiment for kids because it demonstrates how when force is applied it increases its thickness and stickiness due to internal friction, also known as viscosity. This explains to students how an object can be either liquid or solid depending on its conditions, such as temperature and pressure, and the properties of the substance, such as melting point and boiling point. There will be three different experiments at the Science Carnival that will display the liquid and solid phase of the oobleck to the kids at the Science Carnival. The first activity consists of kids playing with the oobleck and punching it and realizing with a great force it turns to solid, but when a student touches it slowly it turns to liquid. The second activity will have an oobleck over a speaker while playing a heavy metal song. This displays different wavelengths and their frequencies. The frequency will show the students how many waves are passing with the wavelength and whether or not the oobleck dances better in high or low frequency. The last activity will let the kids to have the opportunity to walk over a liquid, but with the speed walking it will apply the right amount of force to change the oobleck to a solid. Oobleck is a great way to show students how objects can be in different phases; solid, liquid or gas!
NGSS Standards:
- Science of Motion and Stability: Forces Interactions
- Science of Waves and their Applications for Information Transfer
- Matter and its Interactions
- Science of Waves and their Applications
Grades K-3
A liquid is something that takes the shape of the container that it’s placed in. Some examples of liquids are water, juice or milk. The oobleck is liquid when you gently touch it. A solid is something that can hold its shape. Some examples of solids are a table, a jacket, or a shoe. After hitting the oobleck it becomes a solid. Why? When you push on something it’s called applying pressure. When pressure is applied or when you push on something hard enough, it can change the way it acts, like when playing freeze tag. When you play freeze tag you run around like a liquid and when someone tags/touches/pushes you, you freeze, like a solid, you don’t move. When you hear a sound, there are invisible waves floating through the air that reach your ear so you can hear. You can’t normally see them, but you can see them with the oobleck on the speaker. An example of waves are like the waves at the ocean. Can you make a wave with your hands?
Grades 4-6
A liquid is something that takes the shape of the container that it’s placed in. Some examples of liquids are water, juice or milk. If milk is poured onto the table it would go everywhere and make a mess. The oobleck is liquid when you gently touch it. A solid is something that can hold its shape. Some examples of solids are a table, a cell phone, or a tablet. If a cell phone is placed on a table it’s not going to move. After hitting or speed walking on the oobleck it becomes a solid. Why? When pressure is applied, it can change the way it acts. When you hear a sound, there are invisible waves floating through the air that reach your ear so you can hear. These waves have both a frequency (how quickly they rise and fall) and an amplitude (how high the waves go up). You have probably seen this effect at the beach. You can’t normally see waves of sound, but you can see them with the oobleck on the speaker.
Middle School
In a liquid, molecules are very spaced out and move around. In a solid, molecules are very close together and don’t move due to intermolecular forces. When you hold hands (intermolecular force) with someone (solid) it is more difficult to move around then when you are by yourself (liquid). When pressure is applied to the oobleck, it’s like forcing the molecules to hold hands, causing it to act like a solid. Different songs make the oobleck dance and move differently. This is due to the different wavelengths and frequencies of the music playing.
College Level
Pressure is the ability to apply force to an area and have the force be distributed. When force is applied it increases its thickness and stickiness due to internal friction, also known as viscosity. An object can be either liquid or solid depending on its conditions, such as temperature and pressure, and the properties of the substance, such as melting point and boiling point. When playing with the oobleck and punching it, realize that with a great force it turns to solid, but when the oobleck is touched slowly it turns to liquid. Different frequencies of sound have different energies. Oobleck over a speaker while playing a heavy metal song displays different frequencies and their effect on the oobleck. With some frequencies, the energy causes the oobleck to be more of a solid as a result of the forces on the oobleck. Speed walking on the oobleck will apply the right amount of force to change the oobleck to a solid while walking slowly across the oobleck allows the oobleck to have the consistency of quicksand.