II DOANH NGHIEP SAN PHAM THlAlNG HIED THIET KE CHE TAO BO THI NGHIEM^ TiCH HOP NGHIEN ClJfU CHUYEN DONG THANG, Sljr DUNG DONG HO DEM THdl GIAN NGUYEN LY TI/0NG TAC TIT D 6i mdi phuang phap day bgc Vat[.]
Trang 1II DOANH NGHIEP - SAN PHAM - THlAlNG HIED
THIET KE CHE TAO BO THI NGHIEM^
TiCH HOP NGHIEN ClJfU CHUYEN DONG THANG,
Sljr DUNG DONG HO DEM THdl GIAN NGUYEN LY TI/0NG TAC TIT
D 6i mdi phuang phap
day bgc Vat li theo
hu'dng phat huy tinh
tich cue, tu luc, sang tao ciia
ngu'di hgc, trong d6 hudng cho
bgc sinh, sinh vien tu tay thiet
ke, che tao cac tbi nghiem
mdi c6 sir sang tao dong thdi
khac phuc dugc nhung ban
che ciia mgt so bg tbi nghiem
hien hanh, tich hgp nhieu thi
nghiem trong mgt TBTN de
hgc sinh ciing co, md rgng va
he thong b6a cac kien thirc da
dugc ITnh bgi trong nha trudng
va thuc te cugc song Khong
nbfl'ng vay, ngoai phat buy
kha nang tan dung bieu qua
cac thiet bj san c6 trong nha
trudng va xa bgi, c6n tao cho
hgc sinh hung thii trong viec
thiet ke che tao TBTN mdi
Sau khi nghien cim ngi dung
kien thiic SGK va khao sat cac bg
thi nghiem dang dugc sir dung
trong day hgc phan ca hgc vat
li 10, chiing toi da thiet ke, che
tao TBTN nghien cim chuyen
dgng thang sii' dung dong bo dem
thdi gian theo nguyen ly tuong
tac tu' ( 12V- 50Hz) dugc gdn
ngay tren vat(xe) ma ta khao sat
(binh 1) Vdi bd thi nghiem nay
c6 the sir dung de nghien cim;
PGS.TS Nguyen Manh Thao - Nguyen Thj Dung
Trudng Dqi hge Su phqm Hd Npi
Chuyen dgng tliang deu; Chuyen dgng nhanh dan deu; Djnh luat I Niutan, Djnh luat II Niuton, Djnh luat III Niuton (su tuong tac ciia hai vat trudc khi va cham) va Djnh luat bao toan dgng lugng
Theo ngi dung kien thuc SGK vdi cac bai da neu tren ciia phan
Co bgc Vat li ldp 10, da dat ra cbo chiing toi yeu cau tliiet ke, che tao mgt bg thi nghiem nghien ciixi chuyen dgng thang dam bao dugc cac tieu chi nliu da dugc trinli bay trudc day [1], [2]:
• Bg thi nghiem giiip tao ra mgt vat chuyen dgng thang deu
va bien doi deu
• Chuyen dgng ciia vat dugc ghi lai sao cho tu d6 c6 the xac djnh dugc: tga do, van tdc, gia toe theo thdi gian
• Nghien cii'u djnh luat II Niutan can c6 them ca cau thay doi luc tac dung ma khon can xet den he vat
• Nghien cim djnh luat bao toan dgng lugng can c6 2 vat va cham mem vdi nhau
• Thiet ke nho ggn, tranh cong kenh va phirc tap trong nhan thuc
• Chi can thuc bien mgt lan thi nghiem cho mgt chuyin
Hintt 1: Dong ho dd duffc cai tien,
gan tren xe
dgng, kliong phai thuc hien nhieu lan thi nghiem tuang
tu, de nghien ciru mgt chuyen dgng Dung trudc yeu cau d6, dua tren nguyen vat lieu c6 san tren thj trudng, ciing su trg giiip cua mgt sd may m6c don gian, chiing toi da thiet ke, che tao TBTT^ tich hgp ve chuyen dgng thang Dong bo du'gc cai tien thiet ke nh6 ggn va chinh xac ban, su dung nguon dien I2V- 50Hz dam bao nguyen tac an toan [I],
Bo thi nghif m gom:
• Ngudn dien 12 V 50 Hz
• Dong ho dem thdi gian (0,02 s) da dugc hoan thien nang cap (nb6 ggn va chinh xac ban)
• 1 mang dai 0,9m gan 2 thanh ray kim loai dan dien dugc klioet ranh d trong (rgng 1,5cm, giua bai thanh ray kim loai)
4Z • TAP CHi THIET Bj GIAO DUC - so 72 - 8/2011
Trang 2DOANH NGHIEP - SAN PHAM - THlTdNG HIED II
• 2 xe c6 the trugt vdi ma
sat nho tren thanh ray dong
thdi c6 hai cap banh xe lay dien
12V- 50Hz tu hai thanh ray,
mgt xe co gan rong rgc
• 1 sung cung cap van toe
ban dau cbo xe (dung qua nang
rai vdi do cao khac nhau, khi
can thay doi do ldn ciia lire tae
dung len xe)
• Cac day n6i dien va bang
giSy
• Bg phan thay doi goc
nghieng ciia mang
Tap chi Thiet bj Giao due, so
47, 2009, tr.38-39
Hinh 3a
Hinh 1: Anh cdn lao cua TBTN
• Bg phan do g6c nghieng
cua mang
• Bg phan dd gia trgng ciia
tbi nghiem nghien ciru dinh
luat HI Niuton
Cach tien hanh thi
nghiem:
I Sir dung TBTN tien hanh
tbi ngiem nghien cuu Chuyen
dgng thang deu, Nhanh dan
deu, Djnh luat bao toan dgng
lugng, Djnh luat (1,11) Niuton
(binh 3a, 3b) dugc tiln hanh
theo hudng dan ciia bai ""Thiit
ke chi tgo bp thi nghiim
nghiin ciru chuyin dpng thdng
su dung dong ho dim thdi gian
theo nguyen li tuang tdc tu"
Hinh 3b
2 Sir dung TBTN tien hanh
nghien ciru djnh luat III Niuton
(hinh 4):
Hmh 4
Phuang phap nghien ciru
va tien hanh thi nghiem da
dugc dang chi tiet d bai Thiet
ki chi tgo vd su dung bp thi nghiem Dinh ludt III Niuton di dgy hgc bdi dinh ludt III Niuton trong chirong trinh SGK Idp 10 THPT", Tap chi Thilt bj Giao
due, so 58, 2010, tr.9-10
Ket luan:
TBTN tich hgp nghien ciru chuyen dgng thang sir dung dong ho dem thdi gian gan tren xe da dugc cai tien che tao c6 do chinh xae ban, tien hanh dugc bang loat cac thi nghiem phan ca hgc Vat li Idp
10 THPT TBTN de chl tao, gia thanh thap, an toan, dap iing day dii yeu cau doi thi nghiem sir dung trong cac bai
ve chuyen dgng thang va khac phuc dugc nhieu diem han che ciia cac bg thi nghiem c6 cung mue dich dang sii' dung
va dugc cai tien tong hgp hai TBTN [1], [2] da dugc dang bao trudc day
Bg thi nghiem c6 the pho bien rgng rai tdi cac trudng THPT vdi chi phi thap, de dang trong viee sir dung doi vdi giao vien va bgc sinh
Tai li^u tham khao
1 Nguyen Manh Thao,
pham Thj Trang Nhung, ""Thiet
ke chi tgo bp thi nghiem nghien ciru chuyin dpng thdng
su dung ddng ho dim thdi gian theo nguyen li luong tdc tu"
Tap cbi Thiet bj Giao due, so
47, 2009, tr.38-39
2 Nguyen Manh Thao,
""Thiet ki chi tgo vd su dung bp thi nghiem Dinh ludt III Niuton
de dgy hgc bdi dinh ludt III Niuton trong chuang trinh SGK Idp 10 THPT', Tap cbi Thilt bj
Giaoduc,s6 58,2010,tr.9-10
TAP CHi THI^T B! GIAO DUC • so 72 • 8/2011 • 43