Falling Objects Scientists tend to be very curious about certain phenomena around them. Falling objects is one of these phenomena that has raised up a lot of reflection and experimentation among scientists. Aristotle’s Hypothesis about falling objects: If the object is heavier, then it will fall more quickly. A mass of 10 Kg will fall twice as fast as a mass of 5 Kg. Aristotle was a Greek philosopher. He thought deeply but he did not feel the need to test his hypothesis. Aristotle 384-322 BCE Galileo’s hypothesis about falling objects: If the object is heavier, then it will not fall faster. The motion of falling bodies should be independent of its weight. If they are the same shape they will fall at the same time. Galileo Galilei 1564-1642 Galileo was a renowned Italian scientist who disagreed with Aristotle. According to legend he tested his reasoning experimentally by dropping cannon balls and bullets off the Leaning Tower of Pisa. Sir Isaac Newton, a British Physicist and Mathematician, describes the Theory of Gravity in 1687 2000 years after Aristotle and 35 years after Galileo Gravitational attraction depends on the mass of the two objects and the distance between them. Sir Isaac Newton1623-1747 Problem: Does the mass of a falling object influence the time of the objects free fall? What other factors influence the time of 2 objects falling from the same height? Hypotheses: If a golf ball and a tennis ball are dropped from the same height, then _________________________________________________________________ Two pieces of tin foil are of the same mass; one is flat, the other rolled into a ball. If they are dropped from the same height, then __________________________________________________________________ Material: Procedure: Data: Table 1: Mass of objects Objects Mass Golf ball Ping pong ball Tin foil ball Tin foil sheet Table 2: Time of falling objects at 1 meter and 5 meters Objects Golf ball Ping Pong ball Tin foil ball Tin foil sheet Time (sec) 1meter Trial 1 Trial 2 Trial 3 average Time (sec) 5 meters Trial 1 Trial 2 Trial 3 average Table 3: Reaction error for stop watch 15sec Lowest Highest +/- range Analysis: 1. Compare the falling time for the three balls. Do your results of your experiment support your hypothesis concerning the time of falling bodies? 2. Compare the falling times for the foil ball and foil sheet. Do your results support your second hypothesis? Conclusion: 3. What Factors influence the time of falling bodies? 4. What is the relationship between the time of falling bodies and their mass? 5. Your reaction time with the stop watch is a source of error. Give two ways to compensate for that error. 6. Newton said Gravitational attraction between 2 objects depends on the mass of the objects and the distance separating them. Galileo said that 2 object would fall at the same time even if they had a different mass. Explain how Newton’s theory supports Galileo’s findings.