Qualification > Sciences

phys doubt

<< < (10/10)

Phosu:
A particle is acted upon by two forces F1 and F2 , given by
F1 = (i – 3j) N,
F2 = ( pi + 2pj) N, where p is a positive constant.
(a) Find the angle between F2 and j

how do we find the angle?

astarmathsandphysics:
Cos x =u.v/|u||v|

halosh92:

--- Quote from: astarmathsandphysics on March 28, 2010, 04:08:25 pm ---Cos x =u.v/|u||v|

--- End quote ---

could you expalin in  details plz?

astarmathsandphysics:
F1 = (i – 3j) N,
F2 = ( pi + 2pj) N, where p is a positive constant.
F1.F2=1*p+-3*2p=-5p
|F1|=sqrt(1^2+(-3)^2)=sqrt(10)
|F2|=sqrt(p^2+(2p)^2)=sqrt(5p^2)
cos theta=-5p/sqrt(10)sqrt(5p^2)=5over sqrt(50)=1/sqrt(2)
theta=cos^-1 1/sqrt()=45

Navigation

[0] Message Index

[*] Previous page