It just does.
a stool is a seat with three or four legs but with nothing to support your back or arms while a chair is a piece of furniture to sit on with a back, a seat and four legs
Because the three feet of the tripod are on the same plane, even if one leg is shorter it will not waver or stumble. However, with four legs, if one leg is shorter it will end up in two planes, or two tripods, and will always waver from one plane to the other, thus making the chair/table unstable. Chairs and tables are probably four legged because they are rectangular. If you want a three legged table you would need to have an extra sphere/block that has three legs branching out, and it would be more expensive.
On a four legged chair, if any of the legs are not as long (or longer) as the others, the chair will wobble. On a three legged stoll, if one of the legs are different, the chair will only be uneven or fall over (depending on how drastic the difference is).
The word tripod is probably derived from Greek: from tri for "three" and podos for "foot." Thus the word tripod means literally three footed.Tripods have only three legs because even on an uneven surface something having only three legs will still not wobble, as something with four legs would. Most camera tripods have legs which are adjustable in length to make a strong, level camera platform.
A chair can have four legs (typically a dinning room or kitchen chair). Some chairs have a single column and splayed out feet (typically an office/typist chair that spins). There are three legged stools (traditional milking stools). Armchairs will have four legs.
The answer to the riddle is a chair. A chair has four legs but cannot walk, and when someone is sitting comfortably in it, the weight can cause the chair's "back" to ache or feel strained. Thus, while it fits the description of having four legs, it is an inanimate object rather than an animal.
quadruped, or quadrupedal (although strictly speaking they refer to an animal having four feet).
This is a riddle. The answer is a chair. A chair has four legs but cannot walk, three eyelets (the holes where bolts go) but cannot see, and twenty arms (the armrests) but cannot grab.
there are four (4) feet on a chair exactly
a chair
You will have five chairs if there are four legs on each chair.
We are one chair short.Excuse me, is this chair taken?He climbed on the chair to change the light bulb.He restored the old antique chair and sold it in his shop.