A bullet from a revolver is less than one inch in diameter and is a projectile.
There have been explosive loaded projectiles MUCH smaller than 1 inch- however, as the size of the projectile decreases, the space available for, and the possible weight of, explosives becomes so small as to make the presence of explosives meaningless.
To me, "one-inch-circle" sounds like one inch IS the diameter.
Three 0.50 inch diameter pipes will fit into one 1.50 inch diameter pipe (hypothetically). The 0.50 inch diameters stack on top of each other until you have 1.50 inches!
one inch is one inch; one inch dia refers to one inch diameter of a circle; it is still one inch
6/8 of an inch
28.575mm
Area = pi * diameter * diameter /4 = 3.14 * 1 *1 /4 = approx = 3/4 of square inch
It is because your 1 inch is one circle 1 inch one circle one of each get it.
One inch in diameter.
0.64952
Calculate the sum
One inch diameter.