Civil Engineering - Surveying - Discussion
Discussion Forum : Surveying - Section 6 (Q.No. 36)
36.
The bearing of C from A is N 30° E and from B, 50 metres east of A, is N 60° W. The departure of C from A is
Discussion:
17 comments Page 1 of 2.
Sayeed said:
3 years ago
@Pkota.
The departure formula is Lsin (θ).
The departure formula is Lsin (θ).
John said:
4 years ago
According to me, The correct answer is 12.5m.
(3)
Pkota said:
4 years ago
When we draw triangle ABC, we found angle A,B,C 60,30,90 and AB=50m.
By applying geometry AC = ABcos60---> (1)
And departure of AC will be ACcos60 ---> (2).
From (1) put value of AC in (2) we got;
Departure of AC= (AB cos60) cos60.
50 x 0.5 x 0.5 = 12.5m.
By applying geometry AC = ABcos60---> (1)
And departure of AC will be ACcos60 ---> (2).
From (1) put value of AC in (2) we got;
Departure of AC= (AB cos60) cos60.
50 x 0.5 x 0.5 = 12.5m.
Bhutan said:
4 years ago
I agree with @Philippines.
The Correct answer is 12.5 m.
The Correct answer is 12.5 m.
Arun Kumar Sah said:
5 years ago
It is 50 sin 30 or 50 cos 60.
VimO said:
6 years ago
Right @@Philippines.
B is 50 m east of A, here departure of C with respect to A has to be found hence RB is 30, so sin 30 is correct, but L is not 50. L has to be distance AC, which is from calculation we get it as 25m.
B is 50 m east of A, here departure of C with respect to A has to be found hence RB is 30, so sin 30 is correct, but L is not 50. L has to be distance AC, which is from calculation we get it as 25m.
(1)
Indu said:
6 years ago
Yes, the answer is 12.5 and I agree @Philippines.
Kcube said:
6 years ago
I agree with you @Philippines.
Philippines said:
6 years ago
I think the answer is 12.5m.
The given distance 50m is for line AB , so you cannot use it directly to solve for departure on line CA.
So using the triangle ABC , given the length of AB=50m and the angles can be computed using the given bearings. The side AC can be computed and AC=25m.
Then, the departure of line AC is 25sin(30)= 12.5m.
The given distance 50m is for line AB , so you cannot use it directly to solve for departure on line CA.
So using the triangle ABC , given the length of AB=50m and the angles can be computed using the given bearings. The side AC can be computed and AC=25m.
Then, the departure of line AC is 25sin(30)= 12.5m.
(5)
Tanmoy said:
7 years ago
L sin α = 50 * sin 30 = 25 m.
(1)
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers