FAQs

Scientific notation is a way of expressing very large or very small numbers in a compact form. In scientific notation, a number is written as the product of two numbers: a coefficient and 10 raised to a power.

A knot is a unit of speed used in maritime and aviation contexts, equivalent to one nautical mile per hour. One nautical mile is based on the circumference of the Earth and is equal to one minute of latitude. Specifically, one nautical mile is equivalent to 1.852 kilometers or 1.1508 miles.

Rainfall is often measured in either inches or millimeters. To convert between these two units: To convert inches to millimeters, multiply the number of inches by 25.4 (since 1 inch is equal to 25.4 millimeters). To convert millimeters to inches, divide the number of millimeters by 25.4. For example, 2 inches of rain is equal to 2 × 25.4 = 50.8 millimeters of rain, and 50 millimeters of rain is equal to 50 / 25.4 ≈ 1.97 inches of rain.

Long Ton (Imperial Ton): Used primarily in the UK, a long ton is equivalent to 2,240 pounds (1,016 kilograms). Short Ton (US Ton): Used primarily in the United States, a short ton is equivalent to 2,000 pounds (907.185 kilograms). Metric Ton (Tonne): Used worldwide, a metric ton is equivalent to 1,000 kilograms (2,204.62 pounds).

Celsius and Fahrenheit are two different scales for measuring temperature. They intersect at one point where they read the same value. This occurs at -40 degrees, meaning −40°C = −40°F.

To convert pounds to kilograms, multiply the number of pounds by 0.45359237 (since 1 pound is equal to 0.45359237 kilograms). To convert kilograms to pounds, multiply the number of kilograms by 2.20462. For example, 10 pounds is equal to 10 × 0.45359237 = 4.5359237 kilograms, and 5 kilograms is equal to 5 × 2.20462 = 11.0231 pounds.

To convert liters to gallons, multiply the number of liters by 0.264172 (since 1 liter is equal to 0.264172 gallons). To convert gallons to liters, multiply the number of gallons by 3.78541. For example, 5 liters is equal to 5 × 0.264172 = 1.32086 gallons, and 2 gallons is equal to 2 × 3.78541 = 7.57082 liters.

To convert miles to kilometers, multiply the number of miles by 1.60934 (since 1 mile is equal to 1.60934 kilometers). To convert kilometers to miles, multiply the number of kilometers by 0.621371. For example, 3 miles is equal to 3 × 1.60934 = 4.82802 kilometers, and 10 kilometers is equal to 10 × 0.621371 = 6.21371 miles.

To convert ounces to grams, multiply the number of ounces by 28.3495 (since 1 ounce is equal to 28.3495 grams). To convert grams to ounces, multiply the number of grams by 0.03527396. For example, 4 ounces is equal to 4 × 28.3495 = 113.398 grams, and 200 grams is equal to 200 × 0.03527396 = 7.05479 ounces.

To convert square feet to square meters, multiply the number of square feet by 0.092903 (since 1 square foot is equal to 0.092903 square meters). To convert square meters to square feet, multiply the number of square meters by 10.7639. For example, 100 square feet is equal to 100 × 0.092903 = 9.2903 square meters, and 5 square meters is equal to 5 × 10.7639 = 53.8195 square feet.

To convert cubic inches to cubic centimeters, multiply the number of cubic inches by 16.3871 (since 1 cubic inch is equal to 16.3871 cubic centimeters). To convert cubic centimeters to cubic inches, multiply the number of cubic centimeters by 0.0610237. For example, 10 cubic inches is equal to 10 × 16.3871 = 163.871 cubic centimeters, and 100 cubic centimeters is equal to 100 × 0.0610237 = 6.10237 cubic inches.

To convert hectares to acres, multiply the number of hectares by 2.47105 (since 1 hectare is equal to 2.47105 acres). To convert acres to hectares, multiply the number of acres by 0.404686. For example, 2 hectares is equal to 2 × 2.47105 = 4.9421 acres, and 5 acres is equal to 5 × 0.404686 = 2.02343 hectares.

To convert joules to calories, multiply the number of joules by 0.239006 (since 1 joule is equal to 0.239006 calories). To convert calories to joules, multiply the number of calories by 4.184. For example, 100 joules is equal to 100 × 0.239006 = 23.9006 calories, and 50 calories is equal to 50 × 4.184 = 209.2 joules.

To convert kilowatts to horsepower, multiply the number of kilowatts by 1.34102 (since 1 kilowatt is equal to 1.34102 horsepower). To convert horsepower to kilowatts, multiply the number of horsepower by 0.7457. For example, 5 kilowatts is equal to 5 × 1.34102 = 6.7051 horsepower, and 10 horsepower is equal to 10 × 0.7457 = 7.457 kilowatts.

To convert bar to psi (pounds per square inch), multiply the number of bar by 14.5038 (since 1 bar is equal to 14.5038 psi). To convert psi to bar, multiply the number of psi by 0.0689476. For example, 2 bar is equal to 2 × 14.5038 = 29.0076 psi, and 30 psi is equal to 30 × 0.0689476 = 2.06843 bar.