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Get me into Oxford - Trig problem
A pendulum is swinging through an angle of 80 degrees. The angle X (degrees), between the pendulum and the vertical, at time T, is given by X=a.Cos(60+T degrees).
Find a and the period of the pendulum. My solution for finding a, X=40(deg) when T=0 40(deg)=a.Cos(0) Cos(0)=1 a=40 For the next part i'm unsure of the value for X (160?), and even if I assume any value i've not been taught how to manipulate trig equasions in this form. Thanks, Max. |
#2
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Re: Get me into Oxford - Trig problem
Is this problem part of an Oxford application?
For part b: cos(a+b) = cos(a)cos(b) - sin(a)sin(b) |
#3
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Re: Get me into Oxford - Trig problem
I'm pretty sure this is a physics problem, not a trig problem and most of the info given is unnecessary to solve the period.
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#4
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Re: Get me into Oxford - Trig problem
[ QUOTE ]
Is this problem part of an Oxford application? For part b: cos(a+b) = cos(a)cos(b) - sin(a)sin(b) [/ QUOTE ] Nah, you certainly dont need to use this to find the period. |
#5
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Re: Get me into Oxford - Trig problem
[ QUOTE ]
A pendulum is swinging through an angle of 80 degrees. The angle X (degrees), between the pendulum and the vertical, at time T, is given by X=a.Cos(60+T degrees). [/ QUOTE ] That equation does not describe anything (that is to say it is nonsensical), do you see why? |
#6
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Re: Get me into Oxford - Trig problem
no
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#7
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Re: Get me into Oxford - Trig problem
Ok, I'm a little confused here, a general position equation for SHM is: X=Acos(omega*t + phi)
where A is the amplitude, omega is the angular frequency and phi is the phase angle, which I think we can ignore in this problem. The equation you posted doesn't make sense, cos(60 + T degrees). What is T degrees and what does that 60 represent? Someone correct me if I'm wrong because I'm certainly no expert on this matter but this is my take on the problem. |
#8
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Re: Get me into Oxford - Trig problem
No, sorry I see where the confustion is..(60+T) degrees where T is time in sec. I'm struggling with mathematical notation on the comp.
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#9
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Re: Get me into Oxford - Trig problem
[ QUOTE ]
No, sorry I see where the confustion is..(60+T) degrees where T is time in sec. I'm struggling with mathematical notation on the comp. [/ QUOTE ] it shouldn't be (60 + T) it should be 60T like we stated earlier unless the 60 is not the angular frequency and if that is the case then I'm not sure how to solve this problem. This problem is pissing me off, I got an answer for the period but it seems too small to be correct. Anyone else figure it out? |
#10
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Re: Get me into Oxford - Trig problem
Hint: What's ten kilograms plus eight joules?
SHM: Acos(wt+p) where w is the angular frequency, t the time and p is the phase angle. Although really, a pendulum oscillating through 80 degrees does not exhibit simple harmonic motion, so the whole question is kind of [censored]. |
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