# Civil Engineering - Surveying - Discussion

Discussion Forum : Surveying - Section 1 (Q.No. 49)
49.
Keeping the instrument height as 1.5 m, length of staff 4 m, the slope of the ground as 1 in 10, the sight on the down-slope, must be less than
30 m
25 m
20 m
15 m
Explanation:
No answer description is available. Let's discuss.
Discussion:
26 comments Page 1 of 3.

staff readings visible for staff height of 2.5m so distance is 2.5x10 = 25m.

Slope = 1/10.
HI = 1.5m.

Height of staff = 4.0 m.
Sight = (4-1.5)/(1/10) = 25 m.

Mani said:   8 years ago
@Hitesh.

I'm not getting you, explain clearly.

Dilawar memon said:   8 years ago
0.25 m is the answer as you discussed here.

Salma said:   8 years ago
I'm not getting the answer explain one again.

S.Sarkar said:   8 years ago
Slope 1:10 that means down 1 m for each 10 m distance.

So, 2.5 x 10 = 25 m.

G mahesh said:   7 years ago
How 2.5 came?

Justin said:   7 years ago
Please tell me what is the different betwn downslope an upslope.

Doss said:   7 years ago
The instrument height of 1.5m, staff height 4m so 4 - 1.5 = 2.5m.

Ashish tadewar said:   7 years ago
The Hi is 1.5m so when and staff 4m.
The reading will be 2.5m on staff on plane. The slope being 1 in 10.
2.5 * 10 = 25 on down slope.