With standard meridian as 82° 30' E the standard time at longitude 90° E is 8 h 30 m. The local mean time at the place will be
A. 7 h 00 m
B. 7 h 30 m
C. 8 h 00 m
D. 9 h 00 m
Answer: Option D
This Question Belongs to Civil Engineering >> Surveying
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Which of the following methods of contouring is most suitable for a hilly terrain?
A. Direct method
B. Square method
C. Cross-sections method
D. Tachometric method
A. 750 mm × 900 mm
B. 600 mm × 750 mm
C. 450 mm × 600 mm
D. 300 mm × 450 mm
A. 22° 30'
B. 23° 27'
C. 23° 30'
D. 24° 0'
Step 1
∆L=Local Longitude - Standard Longitude
∆L=90°E - 82° 30' E
∆L=7°30'.
Step 2
CONVERT MINUTES TO ARC TO DEGREE
30'=30/60=0.5°
∆L=7.5°
TIME DIFFERENCE
∆T=∆L × 4 minutes/ degree
∆T= 7.5° × 4 = 30 Minutes
Local mean time =8 h 30 m + 30 m
= 9 h 00 m.