Consider a well which has a swinging bucket of nugatory size dangling from a massless rope- forming a simple pendulum. The rope's initial length is 20 metres, but I begin to winch the rope upwards at a regular rate to a length of 2 metres, which takes one minute. During this time, how many full swings (or oscillations, assuming I start winching when the bucket is at a point of equilibrium) does the bucket complete?

Ignore friction/air resistance, and assume g = 9.8 ms − 2 g=9.8 \text{ ms}^{-2} g=9.8 ms−2.