Civil Engineering - GATE Exam Questions - Discussion

Discussion Forum : GATE Exam Questions - Section 1 (Q.No. 30)
30.
A steady discharge of 1 cumec flows uniformly in a rectangular channel 1 m wide at a depth of 250 mm. The slope of the channel bed is :
adverse
steep
critical
mild
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
19 comments Page 1 of 2.

ABC said:   8 years ago
Yes steep should be the correct answer as critical depth is higher than normal depth.

Type of slope ----- Relation
Mild ----- Yn>Yc
Steep ----- Yn<Yc
critical ----- Yn=Yc
Adverse ----- Slope<0
Horizontal ----- Slope=0.

Where Yn & Yc are normal and critical depth.
(1)

Sadashiva said:   6 years ago
Yc = ((q^2/g))^(1/3) q=Q/B, q=1/1=1.
Yc = ((1 /9.81))^(1/3).
Yc = 0.467m.

Given Yn = 250mm = 0.25m.

Condition when, yc>yn(steep slope).
So, the answer is option B.
(2)

DHAWAL said:   1 decade ago
Answer should be steep, as by calculations, critical depth = 0.46 m; whereas given normal depth is 0.25 m, as critical depth>normal depth so it would be steep.

Ramu said:   10 months ago
Effective depth D = B/2.
B = 1000mm.
Then, D = 1000/2 = 500>250mm.
Hence it's harmful and acting towards Conflict, means Adverse. So it's the right answer.

Bhawna said:   9 years ago
yc = (q2/g)1/3 = 0.46.

Option B is correct because 0.25less than 0.46, critical depth is more means steep slope.

Dixita said:   5 years ago
How to find yn when S is not known? 0.25m is not yn, right? Anyone, please explain in detail.

Praveen said:   1 decade ago
It should be steep slope because critical gradient is more than given depth hence its B only.

Sky said:   8 years ago
Yn= 1 & Yc = (q^2÷g)^1÷3.
Yc= .46.
Yn >Yc.
It is adverse slope.

Manprit said:   9 years ago
Answer B is correct.(q2/g)^1/3 = 0.46, which is greater than 0.25.

Shail said:   10 years ago
Yes @Dhawal, you guys are right it is Steep yc = 0.46 and yn = 1.


Post your comments here:

Your comments will be displayed after verification.