Question on circular motion, finding out the angular displacement in a clock.

AI Thread Summary
To calculate the angular displacement of a clock's hands at 3:30, the minute hand is correctly determined to be at 180 degrees from the 12:00 position. The hour hand, however, is not directly at 90 degrees but rather between 3 and 4, resulting in an angular displacement of 105 degrees. This is calculated by considering the hour hand's position as a fraction of the hour, specifically 3.5/12 of a full circle (360 degrees). The realization that the hour hand is not fixed at 3 but is moving towards 4 clarifies the confusion. Understanding the hour hand's position is crucial for accurate angular displacement calculations.
mutineer123
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Homework Statement


A clock is showing 3.30. Calculate the angular displacement in degrees from the 12.00 position of the clock to:
i the minute hand
ii the hour hand

I got my minute answer as 180 degree, which is right. But my second answer was 90 degrees, which apparently is wrong! the answer theyr giving is 105 degrees! how come? even just looking at the hour hand, we can see that the angular displacement should be 90 degrees! they did something like 3.5/12 X 360 degrees.


Homework Equations





The Attempt at a Solution

 
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When the clock reads 3:30, is the hour hand pointing directly at 3 or is it somewhere between 3 and 4?
 
Jimmy said:
When the clock reads 3:30, is the hour hand pointing directly at 3 or is it somewhere between 3 and 4?

holy crap, u are right. Its btween 3 and 4...I totally overlooked that!
 
It's a bit of a trick question. My first reaction was that the answer is wrong until I thought about it for a few seconds.
 
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