The torque exerted by a force F at a distance r from the pivot point is given by the formula:
τ = F x r x sin(θ)
where θ is the angle between the force vector and the vector from the pivot point to the point where the force is applied.
In this case, the person's weight is the force being exerted on the board, and its magnitude is:
F = m x g = 65 kg x 9.8 m/s^2 = 637 N
The distance from the pivot point to the person is r = 1.5 m. Since the person is standing vertically, the angle between the weight vector and the vector from the pivot point to the person is 90 degrees, so sin(θ) = 1. Substituting the values into the torque formula, we get:
τ = 637 N x 1.5 m x 1 = 955.5 Nm
Therefore, the person is exerting a torque of 955.5 Nm on the diving board with respect to the pivot point.