ok this stupid program is starting to piss me off again (sry for the french)(adsbygoogle = window.adsbygoogle || []).push({});

ok the question is:

What tangential speed, , must the bob have so that it moves in a horizontal circle with the string always making an angle theta from the vertical?

Express your answer in terms of some or all of the variables m, L, and theta, as well as the acceleration due to gravity .

and my answer...after several right answers marked wrong, was sqrt(L*sin(theta)*g*tan(theta)) and i got it right

the next question is:

How long does it take the bob to make one full revolution (one complete trip around the circle)?

Express your answer in terms of some or all of the variables m, L, and theta, as well as the acceleration due to gravity .

easy i thought...i already knew that the radius was going to be L*sin(theta) from the previous problem and so i had the distance and the velocity...piece of cake to get time right? wrong. i entered this for time:

(6.28 *L*sin(theta))/(sqrt(L*sin(theta)*g*tan(theta)))

which basically equates to distance/velocity = time

BUT I GET IT WRONG! WTF?! i am not entering it wrong or anything...any input would be appreciated

attached is the picture for the problem if that helps

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# Homework Help: Stupid masteringphysics again

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