The position vector `vec(r)` of a moving particle at time t after the start of the motion is given by `vec(r) = (5+20t)hat(i) + (95 + 10t - 5 t^(2)) hat(j)`. At the t = T, the particle is moving at right angles to its initial direction of motion. Find the value of T and the distance of the particle from its initial position at this time.

Answer

[5s, 125m]