Inch – Definition, Measurement, Facts, Examples, FAQs

What is an Inch?

An inch (abbreviation: in, symbol: ”) is a unit of length or distance in the US customary system of measurement. 

Foot, yards, miles are other customary units of length/distance. 

12 inches = 1 foot (12” = 1 ft)

36 inches = 1 yard (36” = 1 yd)

63,360 inches = 1 mile (63,360” = 1 mi)

Inch Definition

Inch is a customary unit of length equal to $\frac{1}{12}$ of a foot.

How Long Is an Inch?

To understand how long 1 inch is, let’s take a look at different day-to-day objects that are about 1 inch long.

A paper clip is about 1 inch long. The diameter of the US quarter is approximately equal to 1 inch (0.955 in).

Inch to Centimeter Conversion

A centimeter (cm) is a metric unit of length. If compared with an inch, 1 cm comparatively smaller.

• 1 inch = 2.54 cm
• 1″ = 2.54 cm

To convert a given length from inches to cm, multiply it by 2.54.

To convert a given length from cm to inches, divide it by 2.54.

Example: Convert 40 inches to centimeters.

40 inches = (40 × 2.54) cm = 101.6 cm

Fractions of an Inch

Take a look at the ruler that has markings up to 10 inches. We have highlighted the 1 inch segment from 0 to 1 to show different fractions of an inch. 

How to Measure Inches without a Ruler

If you don’t have a ruler or measuring tape, there are a few methods you can use to estimate or measure an inch:

• Use common objects: Many everyday items have known dimensions. For example, a standard US quarter has a diameter of approximately 0.955 inches, so you can use it to estimate the length of an inch. Other objects with known dimensions, such as credit cards or certain smartphone models, can also be used as reference points.

• Use your hand: On most people, the distance from the tip of the thumb to the first knuckle is roughly an inch. You can use this as a rough estimation by aligning the tip of your thumb with the starting point and counting the number of thumb lengths.

Remember, these methods are approximate and may not provide precise measurements. It’s always best to use a reliable measuring tool, such as a ruler or measuring tape, for accurate measurements when possible.

Different Uses of Inch

• An inch is used to describe the dimensions of TV screens or display screens.
• It is also used to measure the length of smaller objects (such as pencils, paper, etc.). 
• A measuring tape is an easy-to-carry tool used to measure length. It is marked in both centimeters and inches. 

Facts about the Inch

Conclusion

In this article, we learned about the customary unit of length, the inch, its conversion, and usage. Let’s use these concepts and solve some problems.

Facts about Inch

Solved Examples on the Inch Unit

1. Define inches with respect to a meter.

Solution:

We know that 1 inch = 2.54 cm. 

The relationship between meter and centimeter is given by 

100 cm = 1 meter

Thus, 1 cm = $\frac{1}{100}$ m

If 1 cm equals $\frac{1}{100}$ m, then  2.54 cm will be equal to $2.54 \times \frac{1}{100}$ m.

2.54 cm = 0.0254 meter

Thus, 1 inch = 2.54 cm =  0.0254 m

2. Jason has a wooden stick that is 58’’ long. How long is a meter stick in centimeters?

Solution:

1” = 2.54 cm

Thus, $58″ = 58 \times 2.54$ cm

58″ = 147.32 cm

The wooden stick is 147.32 cm long.

3. Which is longer, 24 inches or 2.8 feet?

Solution: 

To compare two measurements, we need to bring them in the same unit.

Let’s convert 24 inches to feet.

12 inches = 1 foot

1 in = $\frac{1}{12}$ foot

$24 \, \text{inches} = 24 \times \frac{1}{12} = 2$ feet

Now, comparing 2 feet and 2.8 feet, we get

2 feet $\lt$ 2.8 feet

Thus, 24 inches is less than 2.8 feet.

4. Convert 87 ft to inches.

Solution: 

1 foot = 12 inches

$87 \, \text{feet} = 12 \times 87$ 

87 feet = 1044 inches

Practice Problems on the Inch Unit

Frequently Asked Questions about the Inch Unit