The greatest and least resultant of two forces acting at a point are 29N and 5N. If each force is increased by 3N, find the magnitude of the resultant of the two new forces when they act at right angles to each other.

Explanation

Given P+Q=29N
P-Q=5N
Adding 2P=34N
`:." " P=17N" and "Q=29-17=12N`
Resultant `R=(P^2+Q^2+2PQcostheta)^(1//2)`
`=(20^2+15^2+2xx20xx15cos90^(@))^(1//2)=sqrt(625)=25N`