An 8 mm mass is roughly one third of an inch. If you look at a ruler, this will give you a good idea of the size of such a mass. There are 2.54 cm or 25.4 mm in one inch. Therefore, 8 mm is just shy of 1/3 inch.
a grain of sugar is about 1 mm. so take three of those and you'll have about 3 mm 3mm is about1/8"
The answer will depend on the units. 20 mm x 8 mm is quite a different size from 20 miles x 8 miles.
If the entire field of view is 32 mm and the object occupies 25% of that then you will multiply 32 by 0.25. The result is 8 mm.
The top are 8 mm and the bottom are 10 mm Remember, that is wrench size.
First off, there are two "types" of needle sizing. The first is the US method of measuring needles, and the second is the UK/Canada method of measuring. Therefore, there are two answers to your question. For US knitting needles, there are sizes: 0 (2.0 mm) 1 (2.25 mm) 2 (2.75 mm) 3 (3.25 mm) 4 (3.5 mm) 5 (3.75 mm) 6 (4.0 mm) 7 (4.5 mm) 8 (5.0 mm) 9 (5.5 mm) 10 (6.0 mm) 10 1/2 (6.5 mm) 11 (8.0 mm) 13 (9.0 mm) 15 (10.0 mm) 17 (12.0 mm) 19 (16.0 mm) 35 (19.0 mm) 50 (25.0 mm) For UK/Canada sizes, there are: 14 (2.0 mm) 13 (2.25 mm) 12 (2.75 mm) 11 (3.0 mm) 10 (3.25 mm) 9 (3.75 mm) 8 (4.0 mm) 7 (4.5 mm) 6 (5.0 mm) 5 (5.5 mm) 4 (6.0 mm) 3 (6.5 mm) 2 (7.0 mm) 1 (7.5 mm) 0 (8.0 mm) 00 (9.0 mm) 000 (10.0 mm)
he's show size is 8
21 mm
A 5.0mm would be an H-8 hook.
0.8 cm IS a description of size it is equal to 8 mm.
A size 8 ring typically has a circumference of about 2.52 inches (or approximately 64 mm). The inner diameter of a size 8 ring is approximately 0.79 inches (or about 20.19 mm). Keep in mind that sizing may vary slightly depending on the ring's design and the manufacturer.
It is in between a 9/16 inch and a 5/8 inch.
An 8 mm circle has a diameter of approximately 0.31 inches, as 1 mm is equivalent to about 0.03937 inches. To visualize, an 8 mm circle is smaller than a standard American quarter, which has a diameter of about 0.95 inches. Therefore, the 8 mm circle is quite compact, roughly one-third the diameter of the quarter.