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snigi
Jun 20, 2009, 12:33 AM
To get resultant displacement of 10m,2 displacement vectors,one of magnitude 6m and the other of 8m should be combined in which way??
a)parallel
b)anti-parallel
c)at an angle of 60
d) at an angle of 90

Unknown008
Jun 20, 2009, 05:06 AM
The easiest way is to try each one.

Parallel, you'll have vector addition, making (8 + 6) m. Does that make 10 m?

Anti parallel, you'll have vector subtraction, making (8 - 6) m. Does that make 10 m?

At an angle of 60 degrees, you'll have to find the resultant by trigonometry, using the cosine rule:

A^2 = B^2 + C^2 - 2(A)(B)cos(a)

Does the resultant give 10 m?

Last one, 90 degrees to each other. Here, no need for the previous formula, just the Pythagoras' Theorem

A^2 = B^2 + C^2

Does that make 10 m?

(Btw, I advise you to use drawings so that you don't get confused)

Hope it helped! :)

snigi
Jun 22, 2009, 08:59 AM
Thanks a lot for the answer..
I knew the answer but had a doubt so I just wanted to confirm...
Thanks anyway

Unknown008
Jun 22, 2009, 09:03 AM
Hey, could you 'rate' my answer please? I'm trying to get green boxes...