# Civil Engineering - Irrigation - Discussion

### Discussion :: Irrigation - Section 2 (Q.No.28)

28.

The Lacey's regime velocity is proportional to

 [A]. R1/2 S3/4 [B]. Q3/4 S1/3 [C]. R3/4 S1/3 [D]. R2/3 S1/2

Explanation:

No answer description available for this question.

 A D said: (Aug 10, 2016) R2/3 S1/3 is this is correct?

 Att said: (Oct 2, 2016) R2/3 S1/2 is correct.

 Md Irshad Alam said: (Mar 27, 2017) According to me, V = 1/n R^2/3 S^1/2.

 Priya said: (Apr 3, 2017) Regime flow equation by Lacey's theory is, V = 10.8.R^2/3.S^1/3. So, Answer (D) and Bed slope (S) to the power of 1/3 not 1/2.

 Sudip said: (Aug 4, 2017) According to Lacey's formula, Regime flow equation V= 10.80 R^2/3 S^1/2.

 Majumder said: (Nov 14, 2017) I agree @SUDIP.

 Ramavtar said: (Jan 9, 2018) Lacey's formula. Regime flow equation V= 10.80 R^2/3 S^1/2.

 Sanath said: (Jan 11, 2018) Correct answer is d.

 Mahe said: (Feb 17, 2018) None of the option is true because according to the formula the powers are 2/3 & 1/3 for R & S respectively.

 Chandu said: (Mar 23, 2018) The Answer is D.

 Sam said: (Apr 24, 2018) D is the correct option.

 Ganesh said: (Jul 18, 2018) Here, V=10.8 R^2/3 S^1/3.

 Chinmoy said: (Jul 19, 2018) You are absolutely right @Mahe. All other answer is based on Manning's formula.

 Musab said: (Aug 17, 2018) The correct answer is R^3/4 S^1/2. R^2/3 S^1/2 is Mannings equation. And other equation by Lacey is 16 R^2/3 S^1/3 used for calculating the flood discharges in rivers.

 Abhisek said: (Oct 12, 2019) Correct and is R^3/4S^1/2.

 Viki said: (Nov 9, 2019) Lacey's regime flow velocity is option (D). nonregime flow velocity option (C).

 Sanjay Nautiyal said: (Nov 21, 2019) Lacey regime flow velocity v = 10.8 R^2/3 S^1/2.

 Hisham said: (Feb 21, 2020) V=10.8 R^2/3 S^1/3. (BC Punmia P. 670).

 Akshay Kumar P said: (Feb 25, 2020) Laceys regime equation is 1/n(r^3/4s^1/3). 10.8r^2/3s^1/3 is laceys theroy.

 Bhagabat Maity said: (Oct 15, 2020) Agree, @ Priya. Option D is correct.

 Prince said: (Aug 7, 2021) There are 2 equations: Lacey's regime velocity: v = 10.8 R^2/3 S^1/2. Lacey's non-regime velocity: v = 1/Na R^3/4 S^1/2. So, the answer should be D.

 Saqib said: (Sep 18, 2021) @Prince There are 2 equations: Lacey's regime velocity: v = 10.8 R^2/3 S^1/3. Lacey's non-regime velocity: v = 1/Na R^3/4 S^1/2.

 Khattak said: (Sep 22, 2021) It should be R^3/4 S^1/2.