Given `vecr = A cos alphat hati + B sin alphat hatj`. Then if `(d^(2) vecr)/(dt^(2))= - alpha^(n) vecr` find the value of n.

Answer

2

Explanation

`vecr= A sin alpha t hati + B sin alpha t hatj`
`(dr)/(dt) = - A alpha sin alpha t hati - B alpha sin alpha t hatj`
`(d^(2) vecr)/(dt^(2)) = - A alpha^(2) cos alpha t hati - B alpha^(2) sin alphat hatj`
`=- alpha^(2) [A cos alpha t hat i + B sin alpha t hatj]`
`=- alpha^(2) vecr`
`therefore n=2`