{"id":4251,"date":"2020-04-16T20:16:08","date_gmt":"2020-04-16T13:16:08","guid":{"rendered":"https:\/\/bacdau.vn\/?post_type=kb&p=4251"},"modified":"2020-04-23T18:32:42","modified_gmt":"2020-04-23T11:32:42","slug":"cong-thuc-tinh-van-toc","status":"publish","type":"kb","link":"https:\/\/bacdau.vn\/kb\/cong-thuc-tinh-van-toc\/","title":{"rendered":"C\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c trong v\u1eadt l\u00fd v\u00e0 to\u00e1n h\u1ecdc"},"content":{"rendered":"
T\u1ed1c \u0111\u1ed9 l\u00e0 kh\u00e1i ni\u1ec7m d\u00f9ng \u0111\u1ec3 ch\u1ec9 \u0111\u1ed9 nhanh c\u1ee7a v\u1eadt th\u1ec3 nh\u1ea5t \u0111\u1ecbnh khi di chuy\u1ec3n m\u1ed9t chi\u1ec1u. Trong l\u0129nh v\u1ef1c to\u00e1n h\u1ecdc, t\u1ed1c \u0111\u1ed9 \u0111\u01b0\u1ee3c hi\u1ec3u l\u00e0 s\u1ef1 thay \u0111\u1ed5i v\u1ecb tr\u00ed c\u1ee7a v\u1eadt th\u1ec3 theo th\u1eddi gian. T\u00f9y v\u00e0o t\u1eebng tr\u01b0\u1eddng h\u1ee3p, b\u1ea1n c\u1ea7n \u00e1p d\u1ee5ng c\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c ph\u00f9 h\u1ee3p \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c t\u1ed1c \u0111\u1ed9 ch\u00ednh x\u00e1c.\u00a0<\/span><\/p>\n Trong v\u1eadt l\u00fd, c\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c c\u01a1 b\u1ea3n \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh nh\u01b0 sau:<\/span><\/p>\n <\/p>\n Trong \u0111\u00f3:<\/span><\/p>\n V\u00ed d\u1ee5:\u00a0<\/span><\/p>\n Anh A c\u1ea7n di chuy\u1ec3n b\u1eb1ng oto t\u1eeb H\u00e0 N\u1ed9i \u0111\u1ebfn Thanh H\u00f3a v\u1edbi kho\u1ea3ng c\u00e1ch 300km. Th\u1eddi gian trung b\u00ecnh \u0111\u1ec3 \u0111\u1ebfn n\u01a1i l\u00e0 3 ti\u1ebfng. V\u1eady v\u1eadn t\u1ed1c \u00f4 t\u00f4 c\u1ea7n di chuy\u1ec3n l\u00e0: 300 \/ 3 = 100 km\/ gi\u1edd<\/span><\/p>\n B\u1ea1n c\u1ea7n hi\u1ec3u r\u1eb1ng, trong qu\u00e1 tr\u00ecnh di chuy\u1ec3n, v\u1eadt th\u1ec3 kh\u00f4ng th\u1ec3 gi\u1eef nguy\u00ean v\u1eadn t\u1ed1c tuy\u1ec7t \u0111\u1ed1i. Do \u0111\u00f3, thay v\u00ec x\u00e1c \u0111\u1ecbnh t\u1eebng v\u1eadn t\u1ed1c kh\u00e1c nhau, m\u1ecdi ng\u01b0\u1eddi s\u1ebd quy \u0111\u1ed5i v\u1ec1 v\u1eadn t\u1ed1c trung b\u00ecnh.<\/span><\/p>\n V\u1eadn t\u1ed1c trung b\u00ecnh \u0111\u01b0\u1ee3c hi\u1ec3u l\u00e0 chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a v\u1eadt th\u1ec3 tr\u00ean qu\u00e3ng \u0111\u01b0\u1eddng \u0111\u01b0\u1ee3c t\u00ednh b\u1eb1ng \u0111\u1ed9 d\u00e0i chia cho th\u1eddi gian \u0111\u1ec3 \u0111i h\u1ebft qu\u00e3ng \u0111\u01b0\u1eddng \u0111\u00f3.<\/span><\/p>\n C\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c trung b\u00ecnh \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng nh\u01b0 sau:<\/span><\/p>\n <\/p>\n Trong \u0111\u00f3:<\/span><\/p>\n \u0110\u1ec3 x\u00e1c \u0111\u1ecbnh t, b\u1ea1n \u00e1p d\u1ee5ng c\u00f4ng th\u1ee9c sau:<\/span><\/p>\n <\/p>\n Trong \u0111\u00f3: v1, v2, v3: V\u1eadn t\u1ed1c di chuy\u1ec3n tr\u00ean qu\u00e3ng \u0111\u01b0\u1eddng s1, s2, s3<\/span><\/p>\n V\u00ed d\u1ee5:\u00a0<\/span><\/p>\n Anh A di chuy\u1ec3n tr\u00ean \u0111o\u1ea1n \u0111\u01b0\u1eddng sau:<\/span><\/p>\n V\u1eady v\u1eadn t\u1ed1c trung b\u00ecnh c\u1ee7a anh A l\u00e0: (50 + 80 + 100) \/ (1 + 1,5 +2) = 57,5 km\/h<\/span><\/p>\n V\u1eadn t\u1ed1c t\u1ee9c th\u1eddi l\u00e0 kh\u00e1i ni\u1ec7m \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 ch\u1ec9 s\u1ef1 nhanh ch\u1eadm v\u00e0 chi\u1ec1u chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a v\u1eadt th\u1ec3 trong th\u1eddi \u0111i\u1ec3m nh\u1ea5t \u0111\u1ecbnh. \u0110\u1ec3 t\u00ednh \u0111\u01b0\u1ee3c v\u1eadn t\u1ed1c t\u1ee9c th\u1eddi t\u1ea1i th\u1eddi \u0111i\u1ec3m c\u1ee5 th\u1ec3, c\u1ea7n x\u00e1c \u0111\u1ecbnh v\u1eadn t\u1ed1c trung b\u00ecnh t\u01b0\u01a1ng \u1ee9ng v\u1edbi nh\u1eefng kho\u1ea3ng th\u1eddi gian nh\u1ecf \u1edf t\u1eebng th\u1eddi \u0111i\u1ec3m:<\/span><\/p>\n C\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c trung b\u00ecnh \u1edf kho\u1ea3ng th\u1eddi \u0111i\u1ec3m nh\u1ecf:<\/span><\/p>\n <\/p>\n C\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c t\u1ee9c th\u1eddi:<\/span><\/p>\n <\/p>\n Trong \u0111\u00f3:<\/span><\/p>\n Ph\u00e9p c\u1ed9ng v\u1eadn t\u1ed1c \u1edf c\u01a1 h\u1ecdc \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong tr\u01b0\u1eddng h\u1ee3p chuy\u1ec3n th\u00f4ng s\u1ed1 v\u1eadn t\u1ed1c sang h\u1ec7 quy chi\u1ebfu kh\u00e1c. C\u00f4ng th\u1ee9c v\u1eadn t\u1ed1c kh\u00e1 \u0111\u01a1n gi\u1ea3n, t\u01b0\u01a1ng t\u1ef1 nh\u01b0 ph\u00e9p c\u1ed9ng vector th\u00f4ng th\u01b0\u1eddng nh\u01b0 sau:<\/span><\/p>\n <\/p>\n Gi\u1ea3i th\u00edch kh\u00e1i ni\u1ec7m:<\/span><\/p>\n C\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c \u0111\u01b0\u1ee3c chia th\u00e0nh nhi\u1ec1u d\u1ea1ng kh\u00e1c nhau bao g\u1ed3m: v\u1eadn t\u1ed1c c\u01a1 b\u1ea3n, v\u1eadn t\u1ed1c trung b\u00ecnh, v\u1eadn t\u1ed1c t\u1ee9c th\u1eddi\u2026 Do \u0111\u00f3, khi gi\u1ea3i c\u00e1c b\u00e0i t\u1eadp li\u00ean quan \u0111\u1ebfn v\u1eadn t\u1ed1c, b\u1ea1n c\u1ea7n x\u00e1c \u0111\u1ecbnh r\u00f5 y\u00eau c\u1ea7u v\u00e0 \u1ee9ng d\u1ee5ng c\u00f4ng th\u1ee9c chu\u1ea9n x\u00e1c, tr\u00e1nh nh\u1ea7m l\u1eabn.<\/span><\/p>\n Xem th\u00eam:<\/i><\/b><\/p>\nC\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c<\/b><\/h2>\n
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C\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c trung b\u00ecnh<\/b><\/h2>\n
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C\u00f4ng th\u1ee9c t\u00ednh v\u1eadn t\u1ed1c t\u1ee9c th\u1eddi<\/b><\/h2>\n
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C\u1ed9ng v\u1eadn t\u1ed1c \u1edf c\u01a1 h\u1ecdc<\/b><\/h2>\n
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