The height of a tower is computed by joining a simple pendulum to its ceiling, whose length is barely adequate to stay off the floor. The pendulum is let go from a small angle, and takes 12 s to return to the similar position it started from.
i) Determine how tall is the tower?
ii) When the pendulum mass is let go 0.3 m above the floor, how fast is the mass travelling as it grazes the floor?