Multiple choice Kaplan water turbine is commonly used when the flow through its runner is axial and the head available is more than 100 m axial and the head available is less than 10 m radial and the head available is more than 100 m mixed and the head available is about 50 m Reveal answer Fill a bubble to check yourself B Correct answer Explanation Kaplan water turbine is a kind of reaction turbine in which axial flow took place & it is used where head available is less than 10 m.