12.101 Golf club velocity and distance A study about the effect of the swing on putting in golf (by C. M. Craig et al., Nature, vol. 405, 2000, pp. 295–296) showed a very strong linear relationship between y = putting distance and the square of x = club’s impact velocity (r2 is in the range 0.985 to 0.999).

a. For the model my = a + bx2, explain why it is sensible to set a = 0.

b. If the appropriate model is my = bx2, explain why if you double the velocity of the swing, you can expect to quadruple the putting distance.