Question 61. For the value of Froude number 9 the jump is said to be strong jump.

Question 62. How many assumptions are made for the derivation of momentum formula?

Question 63. Depending upon the Froude number, into how many groups the jumps are classified?

Question 64. On which surface the energy dissipation is less efficient?

Question 65. The length of the jump is how times the height of the jump?

Question 66. Which of the following is not a limitation of creep theory?

Question 67. Consider the following statements about Bligh’s Creep Theory.
i. Creep length is the length of path traversed by percolating water
ii. To increase the path of percolation vertical cut-off or sheet piles can be provided
iii. Loss of head per unit creep length is hydraulic gradient
iv. Bligh gave no criteria for the safety of weir against undermining
Which of the following statements are correct?

Question 68. According to Bligh, a vertical cut-off at U/s end of the floor is less useful than the one at the D/s end of the floor.

Question 69. If the value of Bligh’s coefficient for a particular soil is equal to 12 then, what is the safe hydraulic gradient for that soil?

Question 70. As per Bligh’s theory, thickness to be provided by taking a factor of safety equal to _______