Cach doi don vi do luong: huong dan day du voi bang va vi du

Doi don vi la ky nang co ban ma chung ta su dung hang ngay ma khong nhan ra. Tu doc cong thuc nau an bang cup khi can nha ban dung gram, den hieu miles per hour tren xe nhap khau hay doi nhiet do tu Fahrenheit sang Celsius. Trong the gioi toan cau hoa noi chung ta mua san pham tu nuoc ngoai, di du lich quoc te va tieu thu noi dung bang nhieu ngon ngu, biet doi don vi can thiet hon bao gio het.

Tren the gioi co hai he do chinh: He do luong quoc te (SI), duoc su dung boi hau het cac nuoc, va he do Anh, duoc su dung chu yeu tai Hoa Ky, Liberia va Myanmar. Su doi nay gay nham lan thuong xuyen, dac biet trong thuong mai quoc te, khoa hoc va du lich.

Voi cong cu doi don vi NexTools, ban co the thuc hien bat ky phep doi nao ngay lap tuc. Nhung hieu moi quan he giua cac don vi mang lai cho ban loi the thuc te to lon.

Do dai la don vi duoc doi nhieu nhat trong cuoc song hang ngay, dac biet giua he met va he Anh:

Tu	Sang	Nhan voi	Vi du
Met	Feet	3,2808	1,80 m = 5,91 feet
Feet	Met	0,3048	6 feet = 1,83 m
Inch	Centimet	2,54	12 inch = 30,48 cm
Kilomet	Mile	0,6214	100 km = 62,14 mile
Mile	Kilomet	1,6093	60 mile = 96,56 km

Meo nhanh:

• Doi km sang mile, nhan voi 0,6. 80 km ≈ 48 mile.
• Doi feet sang met, chia cho 3,3. Nguoi cao 6 feet khoang 1,82 met.
• 1 inch = chinh xac 2,54 cm. Kich thuoc man hinh (55", 65") tinh theo inch duong cheo.

Cac phep doi nay huu ich khi tinh chi so BMI neu so do cua ban dang o he Anh.

Trong luong cung la nguon gay nham lan thuong xuyen giua hai he:

Tu	Sang	Nhan voi	Vi du
Kilogram	Pound	2,2046	70 kg = 154,32 lb
Pound	Kilogram	0,4536	150 lb = 68,04 kg
Ounce	Gram	28,3495	8 oz = 226,80 g
Gram	Ounce	0,0353	500 g = 17,64 oz

Meo nhanh doi kg sang pound: Nhan doi roi cong them 10%. Vi du: 80 kg x 2 = 160, cong 10% (16) = 176 pound. (Gia tri chinh xac: 176,37 lb, sai so duoi 0,3%)

Doi nhiet do la duy nhat vi can cong thuc co phep cong thay vi chi nhan:

Doi	Cong thuc	Vi du
Celsius sang Fahrenheit	F = (C x 9/5) + 32	37°C = 98,6°F (nhiet do co the)
Fahrenheit sang Celsius	C = (F - 32) x 5/9	72°F = 22,2°C (nhiet do phong de chiu)
Celsius sang Kelvin	K = C + 273,15	0°C = 273,15 K

Nhiet do tham khao nhanh:

• 0°C = 32°F (diem dong cua nuoc)
• 20°C = 68°F (nhiet do phong thoai mai)
• 37°C = 98,6°F (nhiet do co the binh thuong)
• 100°C = 212°F (diem soi cua nuoc)

Meo Celsius sang Fahrenheit: Nhan doi roi cong 30. Khong chinh xac nhung cho gia tri gan dung huu ich. 25°C: 25 x 2 + 30 = 80°F (chinh xac: 77°F).

The tich su dung don vi khac nhau cho nau an, nhien lieu va su dung chung:

Tu	Sang	Nhan voi	Su dung
Lit	US Gallon	0,2642	Nhien lieu
US Gallon	Lit	3,7854	Nhien lieu
Mililit	US Ounce long	0,0338	Do uong, thuoc
US Cup	Mililit	236,59	Nau an

Quan trong: US gallon (3,785 L) khac voi gallon Anh (4,546 L). Dieu nay gay nham lan trong cong thuc nau an va thong so nhien lieu giua cac nuoc.

Tuong duong huu ich cho nau an:

• 1 cup = 240 ml (gan dung, tieu chuan nau an)
• 1 muong canh = 15 ml
• 1 muong ca phe = 5 ml
• 1 lit ≈ 4,2 cup

Toc do:

• 1 km/h = 0,6214 mph | 100 km/h = 62,14 mph
• 1 mph = 1,6093 km/h | 60 mph = 96,56 km/h
• 1 hai ly = 1,852 km/h (dung trong hang hai va hang khong)

Dien tich:

• 1 hecta = 10.000 m² = 2,471 mau Anh
• 1 mau Anh (acre) = 4.046,86 m²
• 1 feet vuong = 0,0929 m²
• Can ho 80 m² = 861 feet vuong

Du lieu so:

• 1 KB = 1.024 byte
• 1 MB = 1.024 KB
• 1 GB = 1.024 MB
• 1 TB = 1.024 GB

Tat ca cac phep doi nay deu co trong cong cu doi don vi, ho tro hon 20 danh muc.

He do luong quoc te (SI) duoc chap nhan vao nam 1960 va duoc su dung chinh thuc tai tat ca cac nuoc tren the gioi ngoai tru ba nuoc: Hoa Ky, Liberia va Myanmar. Tuy nhien, ngay ca cac nuoc nay cung su dung SI trong boi canh khoa hoc.

Bay don vi co ban cua SI la:

Dai luong	Don vi SI	Ky hieu
Do dai	Met	m
Khoi luong	Kilogram	kg
Thoi gian	Giay	s
Nhiet do	Kelvin	K
Dong dien	Ampe	A
Luong chat	Mol	mol
Cuong do anh sang	Candela	cd

He tien to SI cho phep bieu dien cac luong rat lon hoac rat nho mot cach don gian: kilo (10³), mega (10⁶), giga (10⁹), mili (10⁻³), micro (10⁻⁶), nano (10⁻⁹).

Day la nhung loi thuong gap nhat va cach tranh chung:

• Nham lan khoi luong va trong luong: Kilogram la don vi khoi luong, pound-force la don vi trong luong. Tren be mat Trai Dat, chung thuc te co the thay the cho nhau, nhung trong vat ly va ky thuat su phan biet la quan trong.
• Khong phan biet US gallon va gallon Anh: 1 US gallon = 3,785 L, 1 gallon Anh = 4,546 L. Xe dat 30 mpg tai My khong giong 30 mpg tai Anh.
• Dung sai muong: Muong canh Australia la 20 ml, trong khi muong My va muong met la 15 ml.
• Lam tron qua som: Trong cac phep doi lien tiep (met sang feet sang inch), giu so thap phan den ket qua cuoi cung.
• Quen rang nhiet do khong phai phep nhan: Ban khong the chi nhan do Celsius voi mot he so de co Fahrenheit. Can cong thuc day du voi phep cong 32.

De tranh sai sot, luon su dung cong cu doi don vi truc tuyen de kiem tra cac phep tinh thu cong cua ban.