Author Topic: HELP! VECTORS (Read 3762 times) Tweet Share

Ken · « **Reply #15 on:** July 08, 2008, 04:48:43 pm »

i reckon the Law of Cosines is beyond physics =/

cara.mel · « **Reply #16 on:** July 08, 2008, 04:51:43 pm »

i reckon the Law of Cosines is beyond physics =/

You don't need it for VCE physics, and the 3rd question guided him to *not* use it.
You can still however use whatever you feel like

hard · « **Reply #17 on:** July 08, 2008, 04:58:44 pm »

what's so hard about the law of cosins. I went to the wikipedia page and it had areas related to the Pythagoras theorem :S.

Mao · « **Reply #18 on:** July 08, 2008, 08:07:07 pm »

what's so hard about the law of cosins. I went to the wikipedia page and it had areas related to the Pythagoras theorem :S.

you REALLY want to use $c^2=a^2+b^2-2ab\cos(C)$ ?

hard · « **Reply #19 on:** July 13, 2008, 11:39:13 am »

c^2=a^2+b^2-2ab\cos(C) when do we use this?

Collin Li · « **Reply #20 on:** July 13, 2008, 12:09:33 pm »

Shouldn't need to use it in Physics, and I never used it in Specialist Maths 3/4, but it's useful to know it I guess.

Mao · « **Reply #21 on:** July 13, 2008, 06:34:32 pm »

Shouldn't need to use it in Physics, and I never used it in Specialist Maths 3/4, but it's useful to know it I guess.

you didn't need to use it in statics?!

Collin Li · « **Reply #22 on:** July 13, 2008, 06:53:22 pm »

Nope, you can just resolve the components.

cara.mel · « **Reply #23 on:** July 13, 2008, 08:16:32 pm »

The last time I used the cosine rule was in year 9

/0 · « **Reply #24 on:** July 13, 2008, 08:17:00 pm »

It's faster than resolving components though, right?

bigtick · « **Reply #25 on:** July 22, 2008, 09:13:06 pm »

c^2=a^2+b^2-2ab\cos(C) when do we use this?

Example Find the resultant of two forces on an object.

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