If the book is placed in the middle, the forces acting on p and q is 5N. If the book is moved 50 cm from q, the forces at p and q can be solved by doing a moment balance
With p as the pivot;
Fq (2 m) = 10 N (0.5 m)
Fq = 2.5 N
Fp = 10 N - 2.5 N = 7.5 N
