TIM HIEU KIEN THL/C
SONG VA XOAY TRONG TANG DOI LlAJ CUA KHI QUYEN
DAO PHU QUYEN
Trirng DHSP Ha Noi
I. Song trong tang ddi lull cua khi quyen
Tren moi khu cao ap ludn hinh thanh nhQng khdi khf rgng Idn cd nhiet do, do am, ap suat tuong ddi ddng nhat. Sau khi hinh thanh, dudi tac dung cua gradlen ap suat khdi khdng khf se di chuyen ve noi ap thap. Neu hai khdi khdng khf tQ noi ap cao cd nhiet do chenh lech nhau va chuyen ddng theo cac hudng hdi tu thi chung se gap nhau va tiep xiic vdi nhau theo mgt mat nghieng nao dd, mat ay dugc ggi la mgt fordng".
Hai ben fordng ap suat, hudng gid khac nhau, tham chf cd the ngugc chieu nhau. Vf du:
Hai ben fordng d vimg dn ddi Bac ban cau gid tQ dia eye thdi ve lech ban sang phfa tay va gid ty ap cao nhiet ddi thdi len lech han sang phia Ddng. Cac ludng gid luan phien thdi hai ben fordng khac nhau lam cac gradien khi ap tac dung len cac phan tQ khf tren fardng ludn thay ddi. Cac phan tQ khf tren fordng bj dao ddng tren cac phudng vudng gdc vdi fordng khi cd gradien khi ap bien thien tac dung. Do tfnh chat dan hdi ciia mdi trudng khi, khi mgt nai nao dd ciia fardng dao ddng thi dao ddng se tQ dd lan truyen ra khap fdrdng theo nhQng ggn sdng dge theo phuang thdi eiia gid. Fardng khdng cd dang mat phang nghieng, bao gid nd cung cd dang lugn sdng.
GiQa cac Idp khdng khi hoac nude chuyen ddng vdi van tdc khac nhau cung ludn cd cac sdng dan hdi lan truyen theo hudng chuyen ddng tuong ddi cua cac Idp dd tuong ty nhu sdng dan hdi lan truyen trong fardng.
Trong mdi trudng khdng khf cdn cd sdng trgng lye. Trgng lye la lye tdng hgp cua lye hut ciia Trai Dat, Mat Trang, Mat Trdi, cac thien the va cac lye quan tfnh do sy ty quay cua Trai Dat gay ra. Do lye hap din ciia Mat Trang, Mat Trdi va cac hanh tinh dat len mgt phan tir ludn thay ddi mgt each gan nhu tuan hoan hang ngay nen tac dung cua trgng lye cung bien thien mgt each tuan hoan. Nguyen nhan nay da lam phat sinh ra cae sdng trgng lye lan truyen trong cac quyen cua Trai Dat. Sdng trgng lye (tQc sdng do trgng lye gay ra) cung la mgt loai sdng dan hdi.
Ngoai sy bien thien tac dung cua gid va trgng lye, eac vat the ran (nhu thien thach, may bay, tau thuy...) chuyen ddng trong khdng khf va trong hai duong cung gay ra cac sdng dan hoi va nhung sdng dd tai ta ed the nghe thay dugc.
ll.Xoay
' farong co nghTa la mat Iran
TIM HIEU KIEN THUC
Khi cd sdng Idn lan truyen trong fardng, nhQng bd phan khdng khi lanh vao sau trong khdi khi ndng va cQng ed nhung bd phan cua khdi khf ndng vao sau trong khdi khi lanh (xem hinh 1).
-^ Ludng khi lanh => Ludng khi ndng ^/\/ fordng Hinh 1
Sy xam nhap ciia cae bd phan thude hai khdi khf vao nhau d hai ben fdrdng tao thanh cae ludi ndng va ludi lanh. Khf lanh tien sau vao phia dudi that ludi ndng lai, cd lap rdi day khf ndng len cao. Trong qua trinh chuyen ddng len cao trong viing khi lanh, theo quan tfnh khdi khi ndng vin chuyen ddng xoay trdn. Tai noi khdng khf ndng chuyen ddng xoay trdn, ap suat thap ban so vdi cae vung xung quanh nen dudi tac dung ciia gradien khf ap cae phan tQ khf xung quanh di chuyen ve phfa bd phan khf ndng. Sy chenh lech khi ap cang Idn thi cac phan tQ khf xung quanh di chuyen ve phfa bd phan khi ndng vdi van tdc cang Idn. Trong qua trinh di chuyen cae ludng khf chju tac dung cua lye quan tinh eoriolis nen di chuyen theo cac dudng cong hinh xoan tao thanh xoay khi (xem hinh 2)
XLL^I
'<^: L,,l
K kt' L^-^h
Hinh 2. Xoay khi
Nhiing xoay khf Idn dudng kfnh dat tdi vai ngan kildmet va van tdc dat tdi hang tram km/h. Khi di qua dai duong, nhung xoay khf nay gay ra nhQng lan sdng Idn lan truyen trong nude.
TJM HIEU KIEN THL/C
d cae ddng chay tren mat dat ta cQng thudng gap cac xoay nude. Do ma sat vdi bd ma nhQng ddng chay gan bd cd van tdc nhd, nhQng ddng xa bd cd van tdc Idn. Sy chenh lech tdc do eua cae ddng nude xa bd va gan bd din tdi sy chenh lech ap suat va sinh ra cac gradien ap suat tac dung len cac phan tQ nQdc lam eac phan tQ nQdc dao ddng theo phuong ngang gay ra sdng dan hdi lan tmyen khap ddng chay. Khi cd sy chenh lech van tdc Idn, cac dinh sdng ngang phat trien thanh eac xoay nude quay trdn quanh true thang dQng va di chuyen theo ddng chay. Cac xoay nude thudng hinh thanh phfa bd sdng Idm (xem hinh 3).
'A s. V*_LSLLI'
Hinh 3. Xoay nUdc phia bd 16m
Ap suat trong xoay nhd nen cac vat de bj day ve phfa xoay, bj nhan chim va mang di xa.
Tai cac bd Idm ciia ddng chay, khi xoay nude di ngang qua se ed mgt lye F = -gradptae dung dot nggt len cac phan tQ ciia bd theo hudng tQ bd ra phia ddng chay. DQdi tac dung eiia lye nay, cac phan tQ eiia bd bi Id khdi bd va dd ve phia ddng chay. Bd Idm cQ bi dao Id dan va bd nay ed vach dyng dQng. Ddng chay tai noi nay ngay cang cong.
Trd lai vdi cae xoay khi. Xoay khi duge hinh thanh tQ mgt ludi ndng bi tach khdi fordng, manh len tao thanh bao. Trong mgt fordng ed the cQ vai ngay lai cd mgt iQdi ndng bj tach ra, rdi hinh thanh mgt con bao. Do vay trong mua mua bao ta vin thudng gap ed nhQng dgt bao lien tiep. Cac xoay khf lien tuc dugc hinh thanh va chuyen di dugc ggi la mgt gia dinh xoay va cae tran bao tQ dd lien tue dQgc hinh thanh ggi la mgt gia dinh bao.
Chu y rang vung gan tam xoay (hoac bao) la vung van tdc gid rat Idn cdn d tam xoay (hoac bao) la vung lang gid. TQ hinh 2 ta biet dugc khi ed bao tran tdi, dau tien gid tQ mdt hudng thdi tdi cQ manh dan len, sau dd gid lang rdi tdi gid ddi chieu thdi theo hudng ngugc lai, dau tien rat manh, gid giat lien tue sau dd van tdc gid giam dan bao hieu can bao sap di qua.
GIAI DAP THAC MAC
Cau hoi: De nghi thay (eo) phan tich ro hdn nhung dac diem eua chiJ' viet tieng Viet va sy' chi phdi eua nhOhg dae diem nay ddi vdi chinh ta d tieng Viet
PGS.TS Do Xuan Thao - TrQdng DHSP Ha Noi tra Idi:
Chu viet tieng Viet thudng duge ggi la chu Quoc ngir, each ggi nay cd tac dung phan biet vdi chQ Han (chQ viet tieng Trung Qud'e) va chQ Ndm (chQ viet duge tao ra tren CO sd ciia chu Han). Chu Han va chQ Ndm tdn tai trong thdi ki phong kien va cd pham vi su dung ban che. ChQ Han la van ty ngdn ngQ chu yeu trong hanh chinh, giao due va mdt sd linh vyc khac nhu: van, sQ, dja... dudi cac trieu dai vua chiia Viet Nam hay chinh quyen dd hd cua phong kien phuang Bac.
ChQ Ndm tuy la mgt thQ chQ qud'e ngQ nhung chua bao gid thye hien dugc chQc nang mdt ngdn ngu qud'e gia thdng nhat. ChQ Ndm dya vao cau tao chQ Han de ghi am tieng Viet.
NhQng ngudi sang tao va sQ dung chQ Ndm thudng van dung nguyen tac cau tao ciia ehu Han theo chu quan, tuy nghi, nen ngay nay, chQ Ndm trong cac van ban cdn luu lai thudng khd hieu, khd dge do each viet khdng thdng nhat Tuy nhien, trong nhung tu lieu ve van hgc nude nha, chung ta van cd nhieu nha van, nha tho nd'i tieng sang tac cac tac pham bang chQ Ndm, dien hinh la Nguyen Du, Ba huyen Thanh Quan, Hd Xuan Huong...
Chu viet tieng Viet {chO Quoc ngu) hien nay ed ngudn gdc Chau Au, dugc du
nhap vao Viet Nam ta tQ dau the ki' XVII. Cac giao si den Viet Nam de truyen dao Co ddc thdi ki dd da nhanh chdng nhan ra rang, cd the diing chQ viet ghi am tieng Viet de hgc tap tieng Viet, su dung tieng Viet vao viec giao tiep vdi ngudi Viet. ChQ viet ciia nhieu ngdn ngQ Chau Au gidng nhau d bd chQ cai Latin (Bd Dao Nha, Phap, y...). Cac giao si thudng lay chQ cai trong bang chQ cai Latin ghi am tieng nude minh de ghi am Idi ndi ma hg cam nhan dugc vdi nhung dieu chinh cu the. Vi the, cd mdt sd trudng hgp, am tieng Viet dugc viet theo nhieu each khac nhau, khdng theo mdt quy tac ghi am thdng nhat nao.
Tinh hinh dd cung gidng nhu viec lay cac bd phan chu de ghi am tieng Viet trong cau tao chQ Ndm. Tuy nhien do chQ Latin la loai chQ viet ghi am thdng nhat ciia cae ngdn ngQ Chau Au nen nhQng each viet khac nhau cung khdng anh hudng den nghia nhu ehu Ndm trudc day.
Dan dan, nhd cdng lao cua cac nha truyen giao, dac biet nhd qua trinh chi'nh sQa va hoan thien ciia mdt sd giao si ngudi Viet, viec ghi am tieng Viet dn djnh theo hudng thdng nhat. He thdng quy tac chinh ta hinh thanh da thay the chQ Han va chQ Ndm, duge nhan dan ta chap nhan va trd thanh cdng cu giao tiep thuan Igi. Tuy nhien do nhQng han che Ijch sQ, dja vj eua chQ Qud'e ngQ cdn phai trai qua mdt thdi gian lau dai ve sau mdi khang djnh dugc la thQ chu viet chfnh thQc ciia mdt dat nude ddc lap va thdng nhat nhu ngay nay.
GIAI DAP THAC MAC
ChQ Qud'e ngQ dQgc day trong nha trudng (theo dudng Idi td chuc va cai each giao due cua thye dan Phap) a Mien Nam ty nam 1879 va Mien Bac ty nam 1906, dugc dua vao tieu chuan tuyen chgn cdng chQc ngQdi Phap va ngQdi Viet thude ngach hanh chinh. Muc dich eua thye dan Phap phd bien chQ Qud'e ngu de lam cdng cu phuc vu chfnh sach cai tri, nhung tren thye te, ket qua dem lai da vugt xa y dinh hep hdi va tham ddc dd.
Chu Qud'e ngQ ngay cang hoan thien de thye hien tdt chye nang giao tiep ciia minh.
Chu Qud'e ngu duge xay dyng tren cd sd eiia bd chQ cai Latin gdm 29 ki ty ed ban.
Ve CO ban moi kf ty dQgc bieu thi bang mdt am vj tQOng Qng trong ngdn ngQ. Vi the, chQ viet tieng Viet la mdt chQ viet dugc ghi am tudng ddi hgp If. 0 cap do am tiet, ndi ehung ed sy ddi yng mdt - mdt giua am va chQ phat am the nao thi viet the ay. Ddi vdi ngudi Viet Nam, cd mdt sd lugng Idn am tiet ma ai cGng cd the viet dung chfnh ta de dang. Nhu vay, ve CO ban ehfnh ta tieng Viet la chinh ta nguT am, giQa each dge va each viet thdng nhat vdi nhau. Trong gid chinh ta, hgc sinh se xae dinh dugc each viet dung (dung chinh ta) bang viec tiep nhan chfnh xae am thanh (vf du: hinh thQc chfnh ta nghe viet). Co che eiia viec viet la xae lap dugc mdi quan he giQa am thanh va chQ viet. Ve mat ly thuyet, trong chinh ta tieng Viet giQa each dge va each viet thdng nhat vdi nhau, cdn trong thye te, sy bieu hien ciia mdi quan he giQa dge (phat am) va viet (viet ehfnh
ta) lai kha phong phu, da dang. Cu the, chfnh ta tieng Viet khdng dya hoan toan vao each phat am thye te eiia mdt phQong ngQ nhat dinh nao. Cach phat am thye te cua cac phQong ngQ deu cd nhQng sai lech so vdi chfnh am, nen khdng the thye hien dQgc theo phuong cham nghe the nao - viet the ay dugc. Thdng thudng, ngudi Viet gap khd khan ve chfnh ta trong hai trudng hgp sau:
* Trudng hgp thir nhat: ChQ viet phan biet each viet hai am tiet nhung trong each phat am phudng ngQ lai khdng phan biet. Vf du, ngQdi ndi phuong ngQ Bac Bd khdng phan biet cac phu am dau eh tr, s - x, d - gi/r... do dd gap khd khan khi phai viet cae tQ cd chQa nhQng phu am dau nay. Vdi ngQdi ndi phQdng ngQ tQ Trung Bd trd vao lai cd van de viet cae phu am cudi la n hay ng, c hay t, viet dau hdi hay dau nga...
* Trudng hgp thir hai: ChQ viet phan biet hai each ghi ma phat am tieng Viet ngay nay khdng cdn phan biet. Dd la trQdng hgp viet phu am dau d hay gi, am chinh / hoac y...
Day cung la nhQng van de chinh ta chung cho mgi mien tren dat nude.
Theo Hoang Phe, tieng Viet hien dai sQ dung 6718 am tiet (cdn ggi la tieng), trong sd dd ed 1075 am tiet (ti le 16%) hoan toan khdng cd van de chfnh ta ddi vdi tat ea cac phuang ngu ( phuang ngu cua mdt mien hoac mdt vai tmh). Ddi vdi tQng vung phuang ngQ, sd am tiet khdng cd van de chfnh ta cang nhieu ban. Vf du, phuang ngu Bac Bd cd:
GIAI DAP THAC MAC
- 575 am tiet cd phu am dau duge viet la ch hay tr, trong dd cd 343 am tiet chQa ch, 232 am tiet chQa tr, 181 trudng hgp cd sy tdn tai ddng thdi cua am tiet chQa ch va tr ddi lap.
Nam dQgc chinh ta cua sd 232 am tiet chQa tr, chu y 181 trugng hgp chQa cap am tiet ddi lap ch/tr [hi ed the suy ra eac trudng hgp khac.
- 535 am tiet chQa s /x.
-111 am tiet chQa iu / uu, ieu / uau.
Tdm lai, vdi mdt ngudi ndi phuang ngu Bac Bd, tdng cdng ed khoang 1950 am tiet (29% tdng sd am tiet) la ed van de chinh ta, nam dugc each viet 1950 am tiet ndi tren tQc la nam duge chinh ta tieng Viet. Ddi vdi
trudng hgp viet phu am dau d hay gi thi tieng Viet chi cd 729 am tiet can viet phan biet.
Nhu vay, vdi tQng phuang ngu, ehi ed mdt sd am tiet nhat dinh la ed van de chinh ta.
Tren thye te, vdi mdi ngudi, sd am tiet cd van de chinh ta lai giam di vi cd rat nhieu nhQng tQ ngQ cu the chiing ta thudng gap, thudng dung, nen da quen viet dung chinh ta. Neu ed mdt phuang phap hgc tap thich hgp va chju khd ren luyen thi ngudi Viet ed the viet dung chinh ta mgt each nhanh chdng, dd dang. Dieu nay khdng dd thye hien ddi vdi nhieu chQ viet tren the gidi nhu tieng Anh, Phap, Han...
Cau hoi: Phan Triet hoe trong mon: "Nhuhg
nguyen iy ecrban cua chu nghia Mac • Lenin"
kho va kha truU tudng, denghj thay (co) chia se cho chung em mgt sdkinh nghiem dehgc tot hoc phan nay.
TS. Nguyen Thj r/;p -TrUdng DHSP Ha Noi tra idi:
Mdn hgc NhUng nguyen ly ca ban cua
chii nghia Mac - Lenin la mdt trong nhQng mdn hgc chung nam trong chuong trinh dao tao ciia tat ca cae he: chinh quy, tai chQc, tQ xa eua cac trugng dai hgc va cao dang hien nay.
Mdn hgc nay d Trudng Dai hgc Su pham Ha Ndi dugc chia lam 2 phan: Nguyen ly 1 (phan
Triet hgc), Nguyen ly 2 (phan Kinh te ehfnh tri va Chii nghia xa hdi khoa hgc).
Mdn hgc Nhitng nguyen ly ca ban ciia chii nghia Mac - Lenin thudng duge ngudi hgc quan niem la mdt mdn hgc khd, khd khan, trUu tugng va dac biet la phan triet hgc.
Thye sy triet hgc cd phai la mdn hgc khd hieu, khd khan, trQu tugng hay khdng? Chac chan khdng phai la nhu vay! Trudc day la mdn triet hgc va bay gid la phan triet hgc trong mdn Nhitng nguyen ly ca ban cua chii nghia Mac - Lenin la mdn hgc dem lai cho ngudi hgc nhung kien thQc rat bd ich, bao quat ve nhieu linh vyc. Vi, triet hgc la he thdng nhung tri thye