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# m3 circular motion

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1. https://160a4a0fd863e9dcf6f7a7eb2ecf...a%20Circle.pdf

Question 5
Why when resolving towards the centre would it be t+tsin theta=mrw^2?
thats what it sais in the mark scheme
2. (Original post by demigawdz)
https://160a4a0fd863e9dcf6f7a7eb2ecf...a%20Circle.pdf

Question 5
Why when resolving towards the centre would it be t+tsin theta=mrw^2?
thats what it sais in the mark scheme
There are multiple Q5's in there.
3. (Original post by Zacken)
There are multiple Q5's in there.
the first question 5 lol
sorry bout that (techinaccly the 2nd question)
4. (Original post by demigawdz)
the first question 5 lol
sorry bout that (techinaccly the 2nd question)
Okay, so there's two things acting radially. One is the tension in the string BR which is of magnitude T and acts in the direction of the centre, so when you resolve you get a term. The other term comes from resolving the tension in the string AR. That has tension radially and vertically. So when you resolve radially you get which is the centripetal force.
5. (Original post by Zacken)
Okay, so there's two things acting radially. One is the tension in the string BR which is of magnitude T and acts in the direction of the centre, so when you resolve you get a term. The other term comes from resolving the tension in the string AR. That has tension radially and vertically. So when you resolve radially you get which is the centripetal force.
oh yeah thanks bro
so two tensions in a string would always have equal tension ?
6. (Original post by demigawdz)
oh yeah thanks bro
so two tensions in a string would always have equal tension ?
Well no, my wording was rather sneaky because when I said "two strings" I really meant "two different parts of the same string" and it's an inextensible string so the tension at any point in the string is the same. i.e: the two different parts of the string have the same tension.
7. (Original post by Zacken)
Well no, my wording was rather sneaky because when I said "two strings" I really meant "two different parts of the same string" and it's an inextensible string so the tension at any point in the string is the same. i.e: the two different parts of the string have the same tension.
ah thanks
8. Ah the lovely days of mechanics...
9. (Original post by demigawdz)
ah thanks
Also - ghostwalker, please jump in if I'm wrong, but I think the tension in both parts of the string is either due to the fact the string is inextensible or the ring at R is smooth.

This is basically the M3 version of M1 pulleys, except with rings.

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