When two forces are acting along the same direction, their resultant is 10N. When the same two forces are acting opposite to each other, their resultant is 8N. Find the forces and their resultant when the angle between them is `45^(@)`

Explanation

Given P+Q=10N
P-Q=8N
`:. 2P=18`
or P = 9N and Q=1N
Hence `R=(P^2+Q^2+2PQcostheta)^(1//2)=(81+1+2xx9xx1(1)/(sqrt2))^(1//2)`
`=sqrt(94.73)=9.73N`