no, they untie because of the force and friction between them
Yes.
Partly, and also due to the pressure that the knott is under once pulled tight.
Although friction slows many things down, and makes machines less efficent, we would have a hard time if there was no friction. Your shoelaces would not stay tied- but that would not matter, since you could not walk if your feet had no friction with the ground- nor could you drive a car- which would be good, since the brakes would not work. You would probably starve since you could not pick up a drink, or food.
Friction and gravity.
The material of the balloon has pores- tiny holes too small to see without a microscope- but big enough to let air molecules slowly escape.
Yes.
yes
Partly, and also due to the pressure that the knott is under once pulled tight.
Allows a car to stop, allows you to walk, your shoelaces to stay tied, nuts to stay on bolts, nails to stay in wood, and allows you to pick up a glass. It also helps keep your pants from falling off.
They will stay tied if you tuck the non looped end under the first tie.
The whole goal with a knot is to create as much friction between each of the strings as possible. The greater the friction, the better the knot will hold. Silk string is very smooth as compared to the cotton string. So the friction produced when a cotton string is tied in a knot is greater than that when a knot tied with silk string. That is why a knot tied with cotton string will hold better than a knot tied with silk string.
Although friction slows many things down, and makes machines less efficent, we would have a hard time if there was no friction. Your shoelaces would not stay tied- but that would not matter, since you could not walk if your feet had no friction with the ground- nor could you drive a car- which would be good, since the brakes would not work. You would probably starve since you could not pick up a drink, or food.
5yrs
Friction and gravity.
Partly, and also due to the pressure that the knott is under once pulled tight.
Pregnancy tests work the same on women with and without their tubes tied.
Sure! "After waiting for hours, she was fit to be tied when her appointment was canceled at the last minute."