Have you ever wondered what happens when you drop two objects of different weights from the same height? At the University of Sydney, an interesting experiment was conducted to explore this question. They wanted to see if a basketball and a 5 kg medicine ball, when dropped at the same time, would hit the ground together or if one would land first. This experiment helps us understand the concepts of gravity and inertia, and challenges what we might think about weight and falling objects.
Before the experiment, people were asked to guess which ball would hit the ground first. Holding a basketball in one hand and a medicine ball in the other, they shared their thoughts. Many thought the heavier medicine ball would fall faster because it weighs more.
As people made their predictions, they considered a few things:
– **Weight Perception**: Many believed that the heavier medicine ball would fall faster. One person said, “The more weight, the faster it’s going to fall to the ground.”
– **Air Resistance**: Some thought about air resistance, suggesting that the lighter basketball might be slowed down more because it’s filled with air.
Even though most people initially thought the medicine ball would land first, some started to rethink their predictions based on physics principles.
After everyone made their guesses, it was time for the experiment. Both balls were dropped at the same time.
Everyone watched closely to see what would happen. Many expected the medicine ball to land first, but when they checked the footage, they were surprised to see that both balls hit the ground almost at the same time.
This surprising result led to a discussion about the physics involved:
– **Gravity and Inertia**: The medicine ball does have more mass, which means a stronger gravitational pull. However, it also has more inertia, meaning it takes more force to get it moving. The basketball, being lighter, has less gravitational pull but also less inertia, allowing it to accelerate similarly.
– **Terminal Velocity**: The balls were not dropped from a height high enough to reach terminal velocity, which is the constant speed that a falling object eventually reaches. If they had been dropped from a greater height, this might have affected the results.
This simple experiment shows us that physics can be surprising. Even though we might think heavier objects fall faster, gravity and inertia work together to make both the basketball and the medicine ball hit the ground at the same time when dropped from a short distance. This experiment reminds us of the importance of questioning our assumptions and exploring the world through scientific inquiry.
Try recreating the experiment at home or in your schoolyard. Gather a basketball and a 5 kg medicine ball, or any two objects of different weights. Predict which one will hit the ground first, then drop them from the same height at the same time. Record your observations and compare them with the results from the University of Sydney experiment. Discuss why the results might be similar or different.
Use an online physics simulation tool to explore the concepts of gravity and inertia. Set up virtual experiments where you can adjust the mass of objects and observe how they fall. Pay attention to how changes in mass affect the speed of falling objects. Write a short report on your findings and how they relate to the real-world experiment.
Divide into two groups and hold a debate on the role of air resistance in the experiment. One group should argue that air resistance significantly affects the falling speed of lighter objects, while the other group should argue that its impact is minimal. Use evidence from the experiment and additional research to support your arguments. Conclude with a class discussion on how air resistance might influence different scenarios.
Learn about terminal velocity and how it applies to falling objects. Use the formula for terminal velocity: $$v_t = sqrt{frac{2mg}{rho C_d A}}$$ where $v_t$ is terminal velocity, $m$ is mass, $g$ is acceleration due to gravity, $rho$ is air density, $C_d$ is the drag coefficient, and $A$ is the cross-sectional area. Calculate the terminal velocity for both the basketball and the medicine ball, assuming they were dropped from a much greater height. Discuss how this might affect the outcome of the experiment.
Work in groups to create a video presentation explaining the physics behind the experiment. Include footage of your own drop experiments, animations or diagrams illustrating gravity and inertia, and interviews with classmates about their predictions and observations. Share your video with the class and discuss what you learned from creating it.
Gravity – The force that attracts a body toward the center of the Earth, or toward any other physical body having mass. – Example sentence: The apple fell from the tree due to the force of gravity pulling it toward the ground.
Inertia – The tendency of an object to resist a change in its state of motion. – Example sentence: Due to inertia, the car continued to move forward even after the driver applied the brakes.
Weight – The force exerted on a body by gravity, calculated as the product of mass and the acceleration due to gravity. – Example sentence: The astronaut’s weight on the Moon is less than on Earth because the Moon’s gravity is weaker.
Air Resistance – The force that opposes the motion of an object through air. – Example sentence: As the skydiver fell, air resistance increased until it balanced the force of gravity.
Experiment – A scientific procedure undertaken to test a hypothesis by collecting data under controlled conditions. – Example sentence: The students conducted an experiment to measure how different surfaces affect the speed of a rolling ball.
Predictions – Statements about what will happen in the future based on current knowledge or hypotheses. – Example sentence: Based on the hypothesis, the scientist made predictions about the outcome of the chemical reaction.
Observations – The act of noting and recording something with instruments or the senses as part of a scientific study. – Example sentence: Careful observations of the plant’s growth were recorded every day during the experiment.
Results – The data and outcomes obtained from an experiment or study. – Example sentence: The results of the experiment confirmed the scientist’s hypothesis about the effect of temperature on solubility.
Terminal Velocity – The constant speed that a freely falling object eventually reaches when the resistance of the medium prevents further acceleration. – Example sentence: A skydiver reaches terminal velocity when the force of air resistance equals the force of gravity.
Mass – The quantity of matter in a body, which is not affected by the force of gravity. – Example sentence: The mass of an object remains the same whether it is on Earth or in space.
