Final answer:
The period of the rocking chair, which completes 11 cycles in 19 seconds, is approximately 1.727 seconds.
Step-by-step explanation:
The period of an oscillation is the time it takes to complete one cycle. In the case of the rocking chair, if a person completes 11 cycles in 19 seconds, we can find the period by dividing the total time of the oscillations by the number of cycles. Therefore, the period T is calculated by T = total time / number of cycles.
Using the given numbers from the question, T equals 19 seconds divided by 11 cycles, which is approximately:
T = 19s / 11 = 1.727s (rounded to three decimal places)
So, the period of the rocking chair is approximately 1.727 seconds.