why plane wings are curved

4:04

15:27

17:27

8:25

4:01

8:28

10:04

9:05

10:22

14:09

4:43

2:40

4:55

3:04

1:56

28:56

29:21

2:57

2:57

2:57

2:27

کوتاه

8:55

1:07

1:11

کوتاه

کوتاه

2:18

کوتاه

9:52

6:23

17:11

2:41

2:35

15:12

2:10

1:36

1:25

1:10

7:01