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Isaac physics & iwantotstudyengineering prep thread

https://isaacphysics.org/

http://i-want-to-study-engineering.org/

Do post your Questions. Happy Interview Prepping !!!

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Great idea!
Thanks I was surprised one of these things didn't exist before
TWO HINGE AND ROD QUESTION
Two uniform rods AB and CD, each of length 6a and mass m are freely hinged together at H where AH = CH = 2a. The rods rest in equilibrium with A and C on a rough horizontal table and at a distance 2a apart. Particles of mass 5m and 4m are suspended from B and D respectively. The coefficient of friction between each rod and the table is μ.
Original post by Duke Glacia
TWO HINGE AND ROD QUESTION
Two uniform rods AB and CD, each of length 6a and mass m are freely hinged together at H where AH = CH = 2a. The rods rest in equilibrium with A and C on a rough horizontal table and at a distance 2a apart. Particles of mass 5m and 4m are suspended from B and D respectively. The coefficient of friction between each rod and the table is μ.


If the question is to find the least value of μ then I think I have an answer..
Original post by MathsAstronomy12
If the question is to find the least value of μ then I think I have an answer..


my working out is the same as their vid it seems but cant seem to find the valueee

Posted from TSR Mobile
Original post by MathsAstronomy12
If the question is to find the least value of μ then I think I have an answer..

What values did you get for Fr
The video partly wrong

Original post by twenty16app
my working out is the same as their vid it seems but cant seem to find the valueee

Posted from TSR Mobile
Original post by Duke Glacia
The video partly wrong


ye so i was assumin the solution is wrong too. ill so it again and post the 2 coefficient values found and see if everyone else got the sams

Posted from TSR Mobile
These are the three equations I got, but my answers contradict each other so double checking:

1) 21mg/2 + R = root(3) x R

2) 17mg/2 + X = root(3) x X

3) R + X = 11mg
Original post by Duke Glacia
What values did you get for Fr


Two values I got were 10root(3)/9 and 10root(3)/13 so least value has to be 10root(3)/9?
Reply 11
Avatar for C0balt
C0balt
16
what level do you recommend to start from
3? or 4
4 should be fine but you can try some from 5 and 6 if youve covered the topic
Original post by C0balt
what level do you recommend to start from
3? or 4
@TeeEm Can you look at the problem ?
Reply 14
Avatar for C0balt
C0balt
16
Original post by Duke Glacia
4 should be fine but you can try some from 5 and 6 if youve covered the topic


cheers
Reply 15
Avatar for TeeEm
TeeEm
19
Original post by Duke Glacia
@TeeEm Can you look at the problem ?


sorry I am teaching all day
Original post by Duke Glacia
I think there is something really wrong with that question both of your ans are more than 1. LOL


I thought the same but apparently: https://www.google.co.uk/#q=can+the+coefficient+of+friction+be+greater+than+1

Don't know what to think..
Original post by MathsAstronomy12
I thought the same but apparently: https://www.google.co.uk/#q=can+the+coefficient+of+friction+be+greater+than+1

Don't know what to think..


Thats right the ans is 1.92.
Original post by Duke Glacia
I think there is something really wrong with that question both of your ans are more than 1. LOL


Let me try it.
Original post by physicsmaths
Let me try it.


Apologies. The question is abso right but just that the coefficient of friction is >1

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