Physics is packed with cool and interesting phenomena that are both fun and educational. Here are five exciting physics experiments you can try, along with explanations of how they work.
To understand the concept of the center of mass, ask a friend to hold a cane or a similar object horizontally. Place your two index fingers together and try to position them underneath the center of mass. When your friend lets go, you might find that it doesn’t balance as expected.
Now, try placing each index finger at opposite ends of the cane and move them towards the middle. You’ll notice that your fingers always end up right under the center of mass, no matter how you start or how quickly you move your fingers. This happens because the center of mass is the point where the mass of the object is balanced, and your fingers naturally move towards that point.
Have you ever tried flipping your phone end over end? You might have noticed that it’s hard to do without the phone also spinning around another axis. When you spin your phone along its long axis, it stays aligned, but flipping it end over end causes it to rotate in other directions. This is due to the conservation of angular momentum and the dynamics of rotational motion, which make a clean flip tricky.
You might have seen a demonstration where rubbing a cup on your hair makes it electrically charged, causing a stream of water to bend when brought close to the cup. While it’s often explained that the polar nature of water causes the molecules to align with the electric field, the reality is more complex.
In a uniform electric field, the forces on the positive and negative sides of the water molecules are equal, so they don’t actually move towards the charged cup. Instead, the attraction happens due to the induced dipole effect, where the electric field influences the distribution of charges within the water molecules, resulting in a net attraction towards the charged object.
For a fun experiment, drop a piece of your favorite cereal into a bowl of water and use a strong magnet to move the cereal around. You might be surprised to find that some cereals are magnetic! This is because of the iron particles in the cereal, which respond to the magnetic field. This experiment shows how everyday objects can have unexpected properties when influenced by magnetic forces.
To make a teabag rocket, carefully cut off the sealed end of a teabag and empty the contents. Stand the empty teabag upright on a plate and light the top on fire. As the fire burns down, the teabag will rise into the air like a rocket. This happens because the burning teabag heats the air inside, causing it to rise and create an upward thrust as the hot air expands and escapes.
These five physics phenomena are not only entertaining but also great demonstrations of fundamental principles in physics. If you’re curious about the science behind these experiments or have your own questions, feel free to share your thoughts or even create a video explaining them!
Try the center of mass experiment yourself! Find a long object like a broomstick. Place your index fingers at each end and slowly move them towards the center. Notice how your fingers meet at the center of mass. Discuss with your classmates why this happens and how it relates to balance.
Grab your phone and attempt the phone flip challenge. Try flipping it end over end and observe the motion. Discuss with your peers why the phone spins in unexpected ways and how angular momentum plays a role. Can you find a way to flip it cleanly?
Charge a plastic cup by rubbing it on your hair, then bring it close to a thin stream of water from a faucet. Observe how the water bends. Discuss with your classmates the concept of induced dipoles and how the electric field affects the water molecules.
Test different cereals to see which ones are magnetic. Place a piece of cereal in water and use a magnet to move it. Discuss why some cereals respond to the magnet and what this reveals about their composition. Can you identify which cereals contain iron?
Create a teabag rocket by following the steps in the article. Observe the rising teabag and discuss with your classmates how the heat causes the air to expand and lift the teabag. Relate this to the principles of hot air balloons and thrust.
Physics – The branch of science concerned with the nature and properties of matter and energy. – In our physics class, we learned about the laws of motion and how they apply to everyday objects.
Mass – A measure of the amount of matter in an object, typically measured in kilograms or grams. – The mass of the rock was measured to be 2 kg using a balance scale.
Experiment – A scientific procedure undertaken to test a hypothesis by collecting data under controlled conditions. – We conducted an experiment to see how different surfaces affect the speed of a rolling ball.
Phone – A device used for communication that can also be used in scientific experiments to measure sound or light intensity. – We used a phone app to measure the decibel level of different sounds in our science project.
Charged – Having an electric charge, which can be positive or negative. – When the balloon was rubbed against the wool sweater, it became charged and stuck to the wall.
Water – A transparent, tasteless, odorless, and nearly colorless chemical substance, essential for most forms of life. – We observed how water changes from a liquid to a gas when heated during our experiment.
Magnetic – Having the property of attracting certain metals, like iron, due to a magnetic field. – The magnetic force of the magnet was strong enough to hold several paperclips.
Cereal – A type of grain used as food, which can be used in experiments to demonstrate density and buoyancy. – We used cereal in our experiment to see which pieces would float in milk and which would sink.
Rocket – A vehicle or device propelled by the expulsion of gases, used for space exploration or scientific experiments. – The model rocket soared into the sky, demonstrating Newton’s third law of motion.
Momentum – The quantity of motion an object has, calculated as the product of its mass and velocity. – The momentum of the moving car was calculated using the formula $p = mv$, where $m$ is mass and $v$ is velocity.
