Which of the following statements is/are correct?
1
Cavitation forms where the local pressure drops up to the vapour pressure conditions due to an increase in local velocity and takes place in turbine blades, runners of pumps, and spillways where local velocity increases considerably.
2
Boundaries likely to be affected by cavitation can be protected against pitting by covering it with tough materials like stainless steel or rubber.
3
Cavitation takes place in turbine blades, runners of pumps, and spillways where local velocity increases considerably. The cavitation may be prevented by raising the ambient pressure relatively higher at probable points of occurrence by raising their levels.
4
Water hammer is a phenomenon which occurs due to high velocity in conduits.