Tiêu đề 01-Direction sense.pdf ✅

Ex.3 Raj walked 20 metres towards South. Then he turned to his left and walked 25 metres. He then turned to his left and walked 20 metres. He again turned to his right and walked 10 metres. At what distance is he from the starting point and in which direction ? (A) 35 metres, East (B) 35 metres, North (C) 40 metres, East (D) 60 metres, East Sol.(A) The movements of Raj are as shown in figure  Raj's distance from starting point A = AE = (AD + DE) = (BC + DE) = (25 + 10) m = 35 m So, E is to the EAst of A Ex.4 Mohan started from his house, walked 2 km North, then 3 km West, then 6 km South. How faraway from his house was he then ? Sol. See the figure. S W N A House C B 3 km 3 km 6 km 4 km 2 km 2 km (AC)2 = (AB)2 + (BC)2 = 9 + 16 = 5 km. Ans. Ex.5 Anil left home and cycled 10 km Southwards, turned right and cycled 5 km & turned right and cycled 10 km and turned left and cycled 10 km. How many kilometres will he have to cycle to reach his home straight ? (A) 10 km (B) 15 km (C) 20 km (D) 25 km Sol.(B) Clearly, Anil starts from home at A, moves 10 km Southwards upto B, turns right and moves 5 km upto C, turns right again and moves 10 km upto D and finally turns left and moves 10 km upto E. Thus, his distance from initial position A = AE = AD + DE = BC + DE = (5 + 10) km = 15 km. Hence, the answer is (B). Ex.6 Amit faces towards North. Turning to his right he walks 25 metres. He then turns to his left and walks 30 metres. Next, he moves 25 metres to his right. He then turns to his right again and walks 55 metres. Finally, he turns to the right and moves 40 metres. In which direction is he now from his starting point ? (A) South-West (B) South (C) North-West (D) South-East Sol.(D) Amit turns towards right from North direction. So, he walks 25 m towards East upto B, turns left and moves 30 m upto C, turns right and moves 25 m upto D. At D he turns to right towards the South and walks 55 m upto E. Next, he again turns to right and walks 40 m upto F. Which is his final position. F is to the South-East of A. A So, he is to the South-East from his starting point. Hence, the answer is (D). Ex.7 From his house, Rajan went 25 kms to the North. Then he turned West and covered 20 kms. Then he turned South and covered 15 Kms/ Finally, turning to East, he covered 20 kms. In which direction was he from his house ? (A) East (B) West (C) North (D) South
Sol.(C) The movements of Rajan are as shown in figure. (A to B, B to C, C to D and D to E) Clearly, his final position is E which is to the C B D E A 25km 15 km 20 km 20 km North of his house at A. Ex.8 A man is facing North-West. He turns 90o in the clockwise direction, then 180o in the anticlockwise direction and then another 90o in the same direction. Which direction is he facing now ? (A) South (B) South-West (C) West (D) South-West Sol. 90o 90o C D B A 180o O As shown in figure the man initially faces in the direction OA. On moving 90o clockwise, he faces in the direction OB. On further moving 180o anticlockwise, he faces in the direction OC. Finally on moving 90o anti- clockwise, he faces in the direction OD, which is South-East. Ex.9 Kishen walks 10 km towards North. From there, he walks 6 km towards South. Then, he walks 3 km towards East. How far and in which direction is he with reference to his starting point ? (A) 5 km, North (B) 5 km, North-East (C) 7 km, East (D) 7 km, West Sol. 10 km 6 km 4 km 3 km D A C The movements of kishen are as shown in figure (A to B, B to C and C to D). AC = (AB – BC) = (10 – 6) km = 4 km. Clearly, D is to the North-East of A.  Kishen's distance from starting point A =AD= 2 2 AC  CD = 2 2 4  3 = 25 =5 km So, kishen is 5km to the North-East of his starting point. Ex.10 A rabbit run 30o towards East and turns to right, runs 20' and turns to right; runs 19' and again turns to left, runs 15' and then turns to left, runs 22' and finaly turns to left and runs 16'. Now, which direction is the rabbit facing ? (A) East (B) West (C) North (D) South Sol.(C) A B D C E F G 16' 15' 30o 19' 22' 20' The movement of the rabbit from A to G are as show in figure. So, the rabbit's face is in North direction at the end of runs. Ex.11 I am facing South. I turn right and walk 20 m. Then I turn right again and walk 10 m. Then I turn left and walk 10 m and then turning right walk 20 m. Then I turn right again and walk 60 m. In which direction am I from the starting point ? (A) North (B) North-west (C) East (D) North-East Sol.(D) The movement of the person are from A to F, as shown in figure. Clearly, the final position is F which is to the Noth-East of the starting point A. E 60 m F 20 m A D 10 m 10 m C 20 m
EXERCISE Q.1 A man is facing south. He turns 135o in the anticlockwise direction and then 180o in the clockwise direction. Which direction is he facing now ? (A) North-east (B) North-west (C) South-east (D) South-west Q.2 A man is facing north-west. He turns 90o in the clockwise direction and then 135o in the anticlockwise direction. Which direction is he facing now ? (A) East (B) West (C) North (D) South Q.3 A man is facing north-west. He turns 90o in the clockwise direction, then 180o in the anticlockwise direction and then another 90o in the same direction. Which direction is he facing now ? (A) South (B) South west (C) West (D) South-east Q.4 I am facing east. I turn 100o in the clockwise direction and then 145o in the anticlockwise direction. Which direction am I facing now ? (A) East (B) North-east (C) North (D) South-west Q.5 Deepak starts walking straight towards east. After walking 75 metres, he turns to the left and walks 25 metres straight. Again he turns to the left, walks a distance of 40 metres straight, again he turns to the left and walks a distance of 25 metres. How far is he from the starting point ? (A) 25 metres (B) 50 metres (C) 140 metres (D) None of these Q.6 Kishenkant walks 10 kilometres towards North. From there, he walks 6 kilometres towards South. then, he walks 3 kilometres towards East. How far and in which direction is he with reference to his starting point ? (A) 5 kilometres West (B) 5 kilometres North-east (C) 7 kilometres East (D) 7 kilometres West Q.7 Gaurav walks 20 metres towards North. He then turns left and walks 40 metres. He again turns left and walks 20 metres. Further, he moves 20 metres after turning to the right. How far is he from his original position ? (A) 20 metres (B) 30 metres (C) 60 metres (D) None of these Q.8 Radha moves towards South-East a distance of 7 km, then she moves towards West and travels a distance of 14 m. From here, she moves towards North-west a distance of 7 m and finally she moves a distance of 4 m towards East and stood at that point. How far is the starting point from where she stood ? (A) 3 m (B) 4 m (C) 10 m (D) 11 m Q.9 Gopal starts from his house towards West. After walking distance of 30 metres, he turned towards right and walked 20 metres. He then turned left and moving a distance of 10 metres, turned to his left again and walked 40 metres. He now turns to the left and walks 5 metres. Finally he turns to his left. In which direction is he walking now ? (A) North (B) South (C) East (D) West Q.10 A girl leaves from her home. She first walks 30 metres in North-west direction and then 30 metres in South-west direction. Next, she walks 30 metres in South-east direction. Finally, she turns towards her house. In which direction is she moving ? (A) North-east (B) North-west (C) South-west (D) None of these Q.11 Sanjeev walks 10 metres towards the South. Turning to the left, he walks 20 metres and then moves to his right. After moving a distance of 20 metres, he turns to the right and walks 20 metres. Finally, he turns to the right and moves a distance of 10 metres. How far and in which direction is he from the starting point ? (A) 10 metres North (B) 20 metres South (C) 20 metres North (D) None of these Q.12 I am facing South, I turn right again and walk 10 m. Then I turn left and walk 10 m and then turning right walk 20 m. then I turn right again and walk 60 m,. In which direction am I from the starting point ? (A) North (B) North-west (C) East (D) North-east