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I need to find the uncertainty on cos(theta) given:

theta = 5 plus/minus 0.1 degrees

what is the uncertainty on cos(theta)? [propagation of error]

2)

Suppose I measured the time taken by the pendulum to complete one oscillation. So the pendulum moves downward and I start the stopwatch. Then the pendulum completes one oscillation and I stop the stopwatch.

Is the ucertainty 0? Lets say my reaction time is 0.17 sec. So, when I see the pendulum move down, I start the clock 0.17 seconds late (which is the time taken by the brain to intrepret the signal). And at the end, I stop the pendulum 0.17 seconds later after the event has occured...

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# Homework Help: Easy: given theta, uncertainity on cos(theta)

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