Bart
Member
Registered: 19th Aug 02
Location: Midsomer Norton, Bristol Avon
User status: Offline
|
hate trig, and this is the only question i got left for my homework this month.
If anyone can help me with it (mainly after the solution+answer) that would be great 
Adam
|
Ian
Site Administrator
Registered: 28th Aug 99
Location: Liverpool
User status: Offline
|
Treat it like its 20mm wide for the whole height of the hole, with a thin right-angle triangle at both sides.
If a is the angle
tan a = opp / adj
opposite is the difference between the sizes of ball, ie. 5, split between two sides = 2.5.
adjacent is the distance between the balls which you can work out fairly easily, 61.44 + 6.10 is the distance between the tops, subtract 12.5 then add 10.
That should get you going on question a)
b) is easy also, just get the angle you find for a) and use toa again, just rewrite it to make opp the subject, ie.
adj (tan a) = opp
None of this is checked btw 
|
drunkenfool
Member
Registered: 7th Feb 03
Location: Hereford Drives: Audi R8 V8
User status: Offline
|
ill have a look when i get back from my lecture if itsnot done then 
|
Bart
Member
Registered: 19th Aug 02
Location: Midsomer Norton, Bristol Avon
User status: Offline
|
ok
|
Bart
Member
Registered: 19th Aug 02
Location: Midsomer Norton, Bristol Avon
User status: Offline
|
anyone else? :-s
|
Ian
Site Administrator
Registered: 28th Aug 99
Location: Liverpool
User status: Offline
|
Just follow my instructions!
How far did you get through them? Anywhere?
|
mike_1.2LS96
Member
Registered: 23rd Oct 03
Location: Darlington | Mazda 323 1.8 Exec
User status: Offline
|
a) tan-1 0.074
b) 61.44 tan (answer a)
there ya go i think.
|
Bart
Member
Registered: 19th Aug 02
Location: Midsomer Norton, Bristol Avon
User status: Offline
|
any chance you could explain the answers mate in great detail?
i really dont get trig that much, and i need to show my working out 
|
Ian
Site Administrator
Registered: 28th Aug 99
Location: Liverpool
User status: Offline
|
Do you know SOHCAHTOA?
|
Nath
Member
Registered: 3rd Apr 02
Location: MK
User status: Offline
|
quote:
Originally posted by Ian
Do you know SOHCAHTOA?
Wow GCSE flashback there
|
Bart
Member
Registered: 19th Aug 02
Location: Midsomer Norton, Bristol Avon
User status: Offline
|
yes, but dont really understand it a great deal.
Sin = opp/adj
cos = adj/hyp
etc
|
Ian
Site Administrator
Registered: 28th Aug 99
Location: Liverpool
User status: Offline
|
Not completely.
If you need to work out an unknown you check what you have first and choose the most appropriate one. Assuming you have the angle of 30, the opposite but not the adjacent then yes:
sin 30 = 5 / adj
Rewrite that to make adj the subject:
adj x (sin 30) = 5
adj = sin 30 / 5
Then just work it out. If you have problems rewriting it, read this a few of these:
http://www.google.co.uk/search?hl=en&q=simultaneous+equations
|
Mistamist
Member
Registered: 16th Jul 03
Location: Gillingham, Kent
User status: Offline
|
quote:
Originally posted by Ian
Do you know SOHCAHTOA?
STOP PLEASE NOW!!!
just saw a vision of my maths teacher Miss Marquiss, she smelt like the gym changing rooms after its raining outside, and im sure she was a close relation of a yeti as she had more facial hair than all of the pubecent lads in her class.
|
