Question

the resultant of two vectors P and Q is R if Q is doubled then the new resultant vector is perpendicular to P vector than R vector is equal to

Answer 1

we know that mod of R is square root of p^2+q^2+2pqcostheta.so when the q is double than mod of R is square root of p^2+4q^2+4pqcostheta.so that is tha value of mod(R).and the deriation of R is tan(alpha)is 2qsin (theta)/p+2qcos (theta ).