# An aircraft took off point A(xºN, 15ºE) at 0720h, local time. It flew due West to another point B(xºN, 75ºW) a distance of 5005 km from A. After a stopover ot 1 hour 30 mimutes at point B. the aircraft took off and flew for 3 hours 40 minutes due South to a point C. The aircraft maintained an average speed of 910 km/h for the journey fom A to B and also from B to C (Take π = 22 and the radius of the earth to be 6370 km) 7

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An aircraft took off point A(xºN, 15ºE) at 0720h, local time. It flew due West to another point B(xºN, 75ºW) a distance of 5005 km from A.
After a stopover of 1 hour 30 minutes at point B, the aircraft took off and flew for 3 hours 40 minutes due South to a point C. The aircraft maintained an average speed of 910 km/h for the journey from A to B and also from B to C
(Take π = 22/7and the radius of the earth to be 6370 km)

1. Calculate the:
• position of point B.
• position of point C
2. Determine the local time at point C when the aircraft arrived.

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1.
1. θ= 75 + 15 = 90
90   x 2 x 22 x 6,370 cos a = 5005
360            7
cos a= 0.500
a= 60
B(60 N, 75W)
2. speed x time= (θ/360) x 2πR
910 x 3hrs 40 mins = (θ/360)2 x 22/7 x 6370
θ= 30
new latitude = 60N − 30 = 30N
C(30 N, 75 W)
2. local time C when departing from A(0720hr)
10   = 4 min
900 =?
90/1 x 4 min = 6hrs
time in c when departing from A
= 0720 hrs − 6 hrs
= 0120 hrs
arrival time = departure time + travelling time
= 0120hrs + 33mins + 1 1/2 + 3hrs 40mins
= 0703 hrs or 7. 03 am