II HirdNG DAN QUAN Li, suf DUNG
Sir DUNG PHAN MEM WORKING MODEL THIET KE THI NGHIEM PHAN CO HOC
TS. Nguyen Dinh Hung - Trudng cao ddng Hdi Duang ThS. Mai Ngoc Anh - Trudng DHHdng Due
1. Tao chuyen dong deu, bien doi deu
a) Tqo chuyen dpng thdng deu theo phuo'ng ngang
Md Working model.
Tren thanh cong cu ciia Working model, kich chgn Rectangle (hinh chu nhat), dua tr6 chugt vao viing lam viec, nhan trai chugt, giQ dong thdi re de ve mgt hinh chu nhat.
Tren thanh menu ciia Working model, kich chgn rotate tool (binh mui ten cuon cong), dat tro chugt vao hinh chu nhat de xoay lam nghieng hinh chQ nhat.
Kich chgn cong cu Rectangle, dua tro chugt vao viing lam viec, nhap trai chugt, giu dong thdi re de ve hinh chu nhat thir hai sao cho mat tren ciia hai hinh chQ nhat tiep xiic nhau.
- Kich chgn r\ut Anchor (mo neo), dua vao viing lam viec, dat tro chugt lan lugt len tung hinh chQ nhat vua ve, nhap trai chugt de co dinh chiing.
Kich diip vao hai hinh chQ nhat, tren menu xo ra thay doi cac gia tri tai 6 Stat.fric, kin.
fric. elastic (su dan hoi, su nay) ve gia trj 0 (sue can khong khi mac dinh bang 0).
Kich chgn niit Circle (hinh tron), dua tro chugt vao viing lam viec, nhap va giQ trai chugt
de ve vat la mgt hinh tron d dinh mat phang nghieng va tiep xue vdi mat phang nghieng.
Nhap chgn vat, tren thanh menu chgn Define tren menu trai ra chgn vectors, tren menu trai ra chgn Velocity.
Acceleration. Quay lai menu Define chgn Vectors display de bien thi vec ta va Vectors lengths de thay doi do dai ciia vec ta. Nhap Run de xem boat canh (hinh 1)
l - i n ^ l l W
Hinhl
De xem do thi mo phong van toe, nhap chgn vat.
Tren thanh Menu nhap chgn Measura/ Postion roi chgn X Graph neu muon mo phong do thi X(t); Measura/ velocity roi chgn Xgraph (neu muon mo phong do thi v^(t); Measura/
Acceleration neu muon mo phong do thi gia toe (hinh 2)
b) Tqo mpt chuyen dpng thdng nhanh ddn deu theo phuong ngang
Md Working model.
Tren thanh cong cu chgn hinh chQ nhat (Rectangle) de
Hinh:
ve len viing lam viec mgt hinh chQ nhat lam mat chuyen dgng.
Kich chgn binh mo neo (Anchor), dua tro chugt dat len binh chu nhat roi nhap trai chugt de cd djnh hinh chu nhat.
Tren thanh cong cu kich chgn hinh tron (Circle) hoac hinh vudng ( Square) hay hinh chQ nhat (Rectangle) de ve mgt hinh tuang iing (vat) dat tiep xiic vdi mat chuyen dgng .
Nhap chgn vat muon tao chuyen dgng. Tren thanh Menu chgn Define thuc hien cac thao tac sau: Define/ Vectors/
Velocity (vec ta van toe) roi Define/ Vectors/ Acceleration (vec ta gia toe); Define/
Vectors/ total Force ( vec to luc tong hgp); Define/ Vectors Display (de hien thi vec to) danh dau kiem vao 6 Name, Value cho cac vec to tuang ung, nhan Ok de hoan tat;
Define/ Vectors lengths (hien thi do dai vec ta)...
Nhap diip len vat. tren Menu dge hien ra dat gia tri y
26
• TAP CHI THIET Bl GIAO DUC • SO 72 - 8/2011HirdNG UAN QUAN Li, sir DUNG
III
= 0; 0 = 0; v^ 7^ 0; V0=O v^ = 0; Stat fric = 0; Kin fric = 0;
Elastic = 0.
Chgn Rectangle ve mgt hinh chQ nhat nho. Tren thanh menu chgn Rotate tool de quay nghieng hinh chQ nhat nay roi dat vao mgt dau binh chQ nhat ldn. Chgn Anchor de cd djnh.
Tao gia trgng: Chgn Square hoac Circle... de ve mgt binh vuong hoac mgt hinh tron.
- Chgn Pulley, dat trd chugt vao hinh tron, re chugt tdi dau tren hinh chQ nhat nho, nhay chugt roi tiep tuc re chugt xuong dudi theo phuong thang dung tdi gap ^ia trgng, nhay dup chugt de ket thiic.
Chgn Polygon de ve mgt gio hun^ gia trgng; chgn Anchor de co dinh gid hung.
De xem do thj md ta van toe, nhap chgn vat; tren menu chinh nhan chgn Measure, dat tro chugt vao Velocity, nhan chgn X Graph.
De xem do thj md ta tga do X, nhan chgn vat; tren menu chinh nhan chgn Measure; dat tro chugt len Position, nhan chgn X Graph.
NhSp Run de xem boat canh. Neu muon dien lai nhap Reset; muon dung nhan Stop(hinb 3)
c) Tqo mot chuyen ddng thdng chdm ddn theo phuffng ngan^
0 o f "
JSI
'U
-A
Ilinh 3
De tao mgt chuyen dgng thang cham dan deu ta lam tuang tu nhu khi tao chuyen dgng thang deu nhung dat gia trj Kin fric ^ 0.
2) Tao mot chuyen dong nem ngang, nem xien, nem theo phu'O'ng thang diing
a) Tqo chuyen ddng nem ngang: Ve mgt mat phang ngang bang cong cu Retangle roi CO djnh n6 bang cong cu Anchor. Bang each tuang tir de ve mat phang ngang thu hai (chgn la mat dat). Ve vat dat len mat phang ngang thir nhat.
Nhap dup len vat. Tren menu dge hien ra chgn v^ i^ 0; neu muon them do thi bieu dien X, y, v^, V lam tuang tu tren.
Nhan Run de xem boat canh b) Tqo chuyen dpng nem xien: Lam tuang tir muc a nhung cbo v , , Vy nhung gia tri khac 0 (v = V v ^ + \ ^). NbSn Run de xem boat canh.
c) Tqo chuyen dpng nem theo phuffng thdng dung:
Lam tuang tu muc a, b nhung thay v^ = 0.
3) Tao tuong tac xuyen tam dan hoi giira hai vat
Ve mgt mat phang ngang bang cong cu Retangle; diing cong cu Anchor de co dinh mat phang ngang;
Dung cong cu Circle ve hai hinh tron (hai vat) dat d hai diem khac nhau tren mat phang ngang;
- Nhap diip len tirng vat, tren menu dge hien ra chgn nhung gia tn thich hgp cho v (irng vdi tirng vat). Neu muon hai
vat chuyen dgng ngugc chieu thi dat v^ ciia mgt vat la duang con V ciia vat kia la am; Chon cac gia trj Kin fric, Stat fric.
Elastic cua hai vat va ciia mat phang ngang bang khong; Vao Meterial de chgn vat lieu cho tung vat (co the ca mat phang ngang); Vao Mass de dat khoi lugng cho tung vat;
De hien thi van toe v.v ta lam nhu cac phan tren.
Nhap Run de xem boat canh. (binh 4)
4. Tao con lac don, con lac 16 xo
a) Tqo con ldc dffn
Ve gia treo con lac bang cong cu Retangle va co dinh n6 bang cong cu Anchor
- Ve vat bang cong cu Circle Ve day treo bang cong cu Rod (nhap chgn cong cu Rod;
dat tr6 chugt vao tam hinh tron, dua tro chugt (theo phuang thang dung) den gap gia treo roi nhap trai chugt).
Nhap trai chugt len vat dong thdi giu' de dua vat ra khoi vi tri can bang.
- Nhap Run xem boat canh.
- De hien thi cac vec ta thuc hien cac thao tac nhu da trinh bay d tren.
b) Tqo con ldc lb xo ddt ndm ngang
Diing c6ng cu Retangle ve mat phang ngang bang va gia giQ dau 16 xo (dat vuong g6c vdi mat phang ngang) roi dung cong cu Anchor de co djnh chiing.
- Ve vat bang cong cu Circle Lan lugt chgn vat va mat phang ngang de chgn cac gia tri Kin fric, Stat fric. Elastic tuang irng bang khong.
TAP CHi THIET Bl GIAO DUC - so 72 - 8/2011 • 27
II HirdNG DAN QUAN U, suf DUNG
Chgn vat; nhap World/
Air Resistnee/ non (mac dinh la non)/ Ok.
Ve 16 xo bang cong cu Spring (Kich chgn Spring, dat tro chugt vao tam vat, dua tro chugt den gap gia dd (theo phuang ngang), roi nhap trai chuot.
llf^^Z :...",.^^vv^
Hmh 5
Dua vat ra khoi vi tri can bang mgt khoang nho
Nhap Run xem boat canh (hinh 5)
Muon bien thj cac vec ta va mo ph6ng bang do thj thuc
hien cac thao tae nhu da gidi thieu d tren.
Sau khi thiet ke xong nhap Save As trong thuc dan file de luu lai.
De sil' dung mo hinh thiet ki c6 hai each: Cach 1; Md Working model roi md eac file da thiet ke de trinh chieu;
Cach 2: Sir dung phan mem Snaglt quay video boat canh de tao mgt file video roi Import n6 vao bai giang Powerpoit hay Hyperlink file video vao mgt vi tri xac dinh tren Slide ciia bai giang Powerpoit.
Phan mem Snaglt download tu http://wwH'.
Snaglt.com.
Su dung phan mem Working Model chiing ta c6 the thiet ke dugc hau bet cac thi nghiem ao cbo phan ca bgc trong chuang trinh vat li pho
t '^'.>.-- * '
Hmh 4
thong. No cho hgc sinh cai nhin true quan ve su thay doi van tdc, gia toe va luc tac dung len vat thong qua viec cho phep hien thi cac vec to d6 va viec md ph6ng bang cac do thi tuang ung.
Tai lieu tham khao:
h t t p ; / / w w w . d e s i g n - simulation.com/wm2d/index.
pbp.
Google/ (PDF) Working model 2D
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TIEN HANH THI NGHIEM.
*»an... Nudc uong c6 gas va nudc n6ng khong the lam Ign ngugc coc nhu tren dugc vi n6 lam tang ap suat d tren chat I6ng va lam tam nhua (hoac bia) rai xuong, chat long se chay xuong het. Cac em hgc sinh chi nen lam thi nghiem vdi nudc cho dan gian va tiet kiem.
Thi nghiem nay khong dugc dimg td bia tham nudc vi khi mat td bia tiep xue vdi nudc ma nudc tham vao thi td bia bi cong, khong ap sat vao mieng coc dugc.
(Tiep theo trang 25)
H2
Chiiy:
Thi nghiem nay c6n mgt sd tru'dng hgp khac:
Neu tam nhua dat vao mieng cdc cd hinh dang nhu d hinh 2 hoac la mgt tam sat mong (loai
v6 hop sQa dac) thi tuy nudc khong day cdc nhung khi Ign ngugc cdc thi tim nay va nudc ben trong cung khong bj roi xudng mac dii Iiic Ign ngugc coc khong CO gigt nudc nao chay ra. Neu nudc ben trong day coc (khong cd bgt khi trong coc) thi van cd the de cdc Ign xuong d tu the nghieng nhung nudc khong chay ra khoi coc. Nhu'ng trudng hgp nay phai giai thich bang kien thii'c d trung bgc pho thong. Khi nao hgc den trung hgc pho thong cac em se van dung de giai thich nhQng hien tugng nay.
28 • TAP CHi THIET Bj GIAO DUC - so 72 • 8/2011
