pi = circumference/diameter
The diameter of a circle is twice its radius and spans the circle passing through its centre.
Use a caliper that's made for inside measurement.
pi was not made - it is not a human artefact. The ratio of the circumference of a circle to its diameter exists independent of human existence.
It depends on the thickness of the material that the pipe is made from.
pi = circumference/diameter
The diameter of a circle is twice its radius and spans the circle passing through its centre.
Diameter of ring=34.1/3.414=9.9cm ( approx 10 cm)
The smallest coin ever produced for circulation by the Royal Mint was 11mm in diameter. The British Halfcrown coin was 32mm in diameter and weighed 14.1 to 14.14 grams when it was made from silver and 14.2 grams when it was made from cupro-nickel.
A diameter is made up of 2 equal radius, so it would be 2 x .9 or 1.8
4cm in diameter
That depends entirely on what material it's made from ! The dimensions are irrelevant unless you tell us what it's made from !
Historically, pencils were made with a diameter of around 7-8mm. Nowadays, standard-sized pencils typically have a diameter of 6-7mm.
No it will not. If I understand your question correctly, the tire you are looking at is 15" in diameter and your rim is 16" in diameter. You need to buy tires that are made for your diameter wheel, 16".
Use a caliper that's made for inside measurement.
A hose is usually made of plastic or rubber. A pipe, on a motor vehicle is made of metal,steel, copper , galvanised. A tube is also made of metal ,but has a much thinner wall . (ie the difference between the outer diameter and the inner diameter)
Actually it's the other way around. Nickels made from 1866 to early 1883 were 20.5 mm in diameter. All nickels made since that time are 21.2 mm in diameter.