Question

if a vector A of magnitude a is rotated by an angle teta from initial direction then the magnitude of change in vector is​

Answer 1

Answer:

(2a) sin(@/2)

Explanation:

form a triangle with two adjacent sides of length 'a' and angle @. now apply sine rule.

in ∆ ABC...AB = AC = a

change = CA = b

^CAB = @ Then..

b/ sin @ = a/ sin (90 -@/2)

i,e..b = sin@ [ a/ sin (90 -@/2) ]

b = (2a) sin(@/2) (upon simplifying)

Note : it's an isosceles and hence the other angles are (90 -@/2) & (90 -@/2)