A visitor to a lighthouse wishes to determine the height of the tower. The visitor ties a spool of thread to a small rock to make a simple pendulum, then hangs the pendulum down a spiral staircase in the center of the tower. The period of oscillation is 9.49 s. What is the height of the tower?

22.38 m

Explanation:

Using,

T = 2π√ (L/g) ... Equation 1

Where T = period of the oscillation, L = Length of the pendulum,/Height of the tower. g = acceleration due to gravity.

Make L the subject of the equation

L = gT² / (4π²) ... Equation 2

Given: T = 9.49 s, g = 9.8 m/s², π = 3.14

Substitute into equation 2

L = 9.8 (9.49²) / (4*3.14²)

L = 22.38 m

Hence the height of the tower = 22.38 m