Pendulum Swing ```Name: N/A Status: N/A Age: N/A Location: N/A Country: N/A Date: N/A ``` Question: A grandfather clock with a metal pendulum is located on a person's deck. Can you explain why the clock loses time in the summer and gains time in the winter. Replies: Assuming a grandfather clock would fit on a desk (high ceilings??), you should consider the following: The ability to keep time is regulated by the pendulum. Because the only forces acting on the pendulum (earth's gravity and the driving spring) are constant the time it takes to swing from left to right and back again depends only on the length of the pendulum. One seasonally dependent variable that could impact the length of the pendulum is temperature. Would the pendulum be longer or shorter in the heat of summer? How would this impact the time it takes the pendulum to swing? How does modern air conditioning impact this? Assuming a grandfather clock would fit on a desk (high ceilings??), you should consider the following: The ability to keep time is regulated by the pendulum. Because the only forces acting on the pendulum (earth's gravity and the driving spring) are constant the time it takes to swing from left to right and back again depends only on the length of the pendulum. One seasonally dependent variable that could impact the length of the pendulum is temperature. Would the pendulum be longer or shorter in the heat of summer? How would this impact the time it takes the pendulum to swing? How does modern air conditioning impact this? Bradburn Click here to return to the Physics Archives

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