About which point does a thrown ball naturally spin? A. Center of gravity B. Starting point C. Highest point D. Lowest point

The answer is A: the center of gravity.

This rests on the assumption that the ball is thrown in real space where gravity is a given phenomena that exists.

It is difficult to theorise about the way the ball would spin, if indeed it would spin at all, if it were weightless. What could be said is that the ball would appear to be moving away, from the point of view of the person throwing it. Equally, the person throwing it would appear to be moving away from the ball, to any observer that might be sharing the balls perspective.

Deep in space, in places far from massive bodies (with gravitational pull), near weightlessness might be experienced. Total weightlessness however may be just a concept.

When a ball is thrown on Earth (Earth is a massive object in space, from our point of view at least), it has been found that the flight of the ball follows a path such that its center of gravity runs along a parabola, the parabola curving down to the ground. This is a smooth process - balls in flight never 'judder', unless they be buffeted by the wind or bump into other objects - so that it must be that the ball is rotating smoothly about the center of it that is following the smooth parabolic path. Which is to say, it must be rotating somehow smoothly about its center of gravity.

The center of gravity of an object can be located by hanging the object from a string, known as creating a 'plumb line'. Following straight down from where the string is attached to the ground (the direction gravity pulls to), we know that (for regular objects, specifically with no holes) the center of gravity is somewhere on that line. The spot is then more precisely located by lowering the object directly to the ground. If it falls over when the string is removed, the center of gravity is more than half way up. Experimenting with placing the object in various ways upon the ground and seeing when it does and doesn't fall or teeter allows closer and closer location of the balance point, ie the center of gravity.

For a regular spherical ball with even density (unbiased weight) the center of gravity is in the very center of the ball whichever way it is placed on the ground. Only if the ground is sloped, or there is insufficient friction somehow to hold the ball in place, will it move.

Answer A: the ball spins naturally about its center of gravity. [For balls, the center of gravity is simply the center of the ball].

Is there a word/phrase for "unperformant"?

As a software engineer, I need to sometimes describe a piece of code as something that lacks performance or was not written with performance in mind. Example: This kind of coding style leads to unmaintainable and unperformant code. Based on my Google searches, this isn't a real word. What is the correct way to describe this? EDIT My usage of "performance" here is in regard to speed and efficiency. For example, the better the performance of code the faster the application runs. My question and example target the negative definition, which is in reference to preventing inefficient coding practices. Answer This kind of coding style leads to unmaintainable and unperformant code. In my opinion, reads more easily as: This coding style leads to unmaintainable and poorly performing code. The key to well-written documentation and reports lies in ease of understanding. Adding poorly understood words such as performant decreases that ease. In addressing the use of such a poorly ...

A man has a garden measuring 84 meters by 56 meters. He divides it into the minimum number of square plots. What is the length of the square plots?

We wish to divide this man's garden into the minimum number of square plots possible. A square has all four sides with the same length.Our garden is a rectangle, so the answer is clearly not 1 square plot. If we choose the wrong length for our squares, we may end up with missing holes or we may not be able to fit our squares inside the garden. So we have 84 meters in one direction and 56 meters in the other direction. When we start dividing the garden in square plots, we are "filling" those lengths in their respective directions. At each direction, there must be an integer number of squares (otherwise, we get holes or we leave the garden), so that all the square plots fill up the garden nicely. Thus, our job here is to find the greatest common divisor of 84 and 56. For this, we prime factor both of them: `56 = 2*2*2*7` `84 = 2*2*3*7` We can see that the prime factors and multiplicities in common are `2*2*7 = 28` . This is the desired length of the square plots. If you wi...

nouns - what do you call the person who passes the trophies to the prize giver/presenter?

The person who gives out the trophies to the winners are called award presenters. So what do u call the person who passes the trophies to the presenter? Thanks!

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