Question

7. Chapter 8: Exercise 66 on page 273, part A only (5 marks)

Pendulum: A student experimenting with a pendulum counted the number of full swings the pendulum made in 20 seconds for various lengths of string. Her data is shown here.

Length (In.)	6.5	9	11.5	14.5	18	21	24	27	30	37.5
Number of Swings	22	20	17	16	14	13	13	12	11	10

A) Explain why a linear model is not appropriate for using Length of a pendulum to predict the number of Swings in a 20 seconds period.

Answer 1

A)

From the above scatter plot, the length of a pendulum is not linearly related to the number of Swings in a 20 seconds period. Here, the relationship is quadratic because the plot has a curve. Hence, a linear model is not appropriate for using Length of a pendulum to predict the number of Swings in a 20 seconds period