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Maths Extension 2 thoughts (5 Viewers)

apurba

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lmao, i like how for the probability of q16 b. pretty much gives you the answer to a.
I worked that out in the last 2 minutes. I ended up getting (i)
but I didn't get enough time to do (ii) when it was the same thing again ahah
 

InteGrand

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Where did you guys get the idea of mu being a variable from?
Well if it's the coefficient of friction, then little v would have been the maximum speed the car can travel without slipping up (i.e. a fixed speed for the given radius). Unless we are told that V is this speed (which we weren't), why are we letting v = V to do the question?

 
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Physicklad

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Where did you guys get the idea of mu being a variable from?
no its not a variable. but i was thrown off by the equation we had to prove because in physics the static coefficient time the normal represents the maximum frictional force that can be provided, so the v they used in the first part was clearly the 'breaking point' past which the car would slide off the track. but then we had to use a different value of v in the next part but still with the same equation. THATs wrong. i ended up just gritting my teeth and believing their bullshit in the end
 

deboiz

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OH HAHAHA yeah mu is a variable, because it's static friction - the friction only exists as much as needed to keep it from moving. But you didn't need to know that realllly to solve the quesiton.
 

Mikes

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Would a 71 align to 85, considering the test was easier than previous years?
 

Physicklad

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OH HAHAHA yeah mu is a variable, because it's static friction - the friction only exists as much as needed to keep it from moving. But you didn't need to know that realllly to solve the quesiton.
dude. how is mu a variable? you of all people should know ;)
 

deboiz

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dude. how is mu a variable? you of all people should know ;)
bro wellllllll we might be getting into definitions here, what i'm saying is that frictional force varies with speed HAHAH you can say that muN is the max friction and that would mean its not a variable LOL

P: P:
 

InteGrand

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OH HAHAHA yeah mu is a variable, because it's static friction - the friction only exists as much as needed to keep it from moving. But you didn't need to know that realllly to solve the quesiton.
Coefficient of static friction is a constant for two given surfaces. If you knew about this, I think the question as given could confuse you.

What you are referring to by ''the friction only exists as much as needed to keep it from moving'' is the frictional force; yes, this depends on the speed. I think the question was just interested in the ratio between the friction (variable depending on speed) and the normal force. This is not what coefficient of friction is, so it would have been best to avoid μ as the symbol in my opinion.
 

Physicklad

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bro wellllllll we might be getting into definitions here, what i'm saying is that frictional force varies with speed HAHAH you can say that muN is the max friction and that would mean its not a variable LOL

P: P:
good boy
 

mrpotatoed

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the complex number stuff had to be all graphed on the same diagram right? the z, u and v stuff
 

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