Yes, that’s exactly what they’re doing…falling horizontally fast enough that they miss the earth due to its curvature. That’s what puts an object in orbit. For a bullet to do the same thing, you’d need to have it in orbit too. You can’t have a bullet in orbit around the earth within the atmosphere due to wind resistance and friction. I’m not sure of the term that’s used for the speed to reach orbit at a certain angle. I was thinking it was “Escape Velocity,” but I believe that’s the speed needed to avoid the gravity of the earth entirely (ie, avoid going into orbit.)
You ever gotton to the end of a page and posted, only to realize later there are additional pages that have ALREADY explained your answer in excruciatingly pleasant logic?
My ego just encountered a mind-numming one-two punch.
Here’s my science question that no one has ever been able to answer:
When you charge up an object with static electricity, why do you need to use a natural fiber (running a comb through your hair, rubbing it with a piece of fur, etc.)? Does a natural fiber somehow move electrons easier than, say, polyester or nylon?
The bottom of the ball is moving faster with respect to the air in the ballpark and this does involve the Bernoulli principle, but remember that air resistance is a function of speed. The bottom of the ball is moving faster so has a higher air resistance, this produces a ‘buildup’ of air at the bottom compared to the top. This ‘buildup’ at the bottom actually means that air is moving across the top of the ball faster than the bottom. And Bernoulli says that means lower pressure at the top, so it climbs.
Don’t confuse the air around (and moving with) the ball with the air elsewhere. I think that is where your confusion comes from.
Note to self: in the future, try to resist kicking people when they’re down. (Even if does make me feel better about continued confusion regarding spinning baseballs.)
I have trouble with string theory, too. Have they got the calculations to collapse to 10 dimensions yet? or is it still 24 dimensions? or is it infinite dimensions?
From a Sydney poster:
When you look at a full moon (next one in 7-8 days time) from Sydney, most of the grey patches (the mare, or lava fields) stretch from about the 6 o’clock to the 10 o’clock positions. We don’t see a “man in the moon”, as the moon’s disc has been rotated; due to our angle of incidence from the direction of the moon.
Here’s one that puzzles me: light travels very fast - 186000 miles / second. When you look at something just above a fire, the image ripples, due to the heat in the air above the fire. But how can this affect light, due to its high speed? Since light travels in a vacuum, it doesn’t need a medium (eg air) to travel in, as sound does. So, to my thinking, the movement of air above the fire shouldn’t affect the passage of light.
Anyone?
Light can travel in a vaccuum, and doesn’t need a medium to travel in, but that doesn’t make it impervious to the media it does travel through. Otherwise glasses wouldn’t work. And lightshades wouldn’t keep out the light, would they?
The light is affected by the movement of the hot air above the fire.
Light is NOT affected by the movement of air. If it was, windy days would be like an acid trip.
Light is affected by the changes in density of the air.
Hot air off the flame is less dense, so has a different index of refraction. This refraction index makes a difference in how fast light travels through the medium.
When the hot and cold air begin to mix above the flame, the bounderies between the hot and the cold (less dense and dense)air bend the light (like the boundy between glass and air, water and air, water and glass, etc…) and gives off the rippling effect you mention.
There used to be this old guy named Hero that postulated that light will travel in whatever path will get it there fastest. Because it can get through the less dense (warm) air quicker, if needed, it will take a detour from a straight path, to get into the less dense air, and then be on it’s way…
How does the light know which path will get it there fastest??? you may ask. It doesn’t, any more than water knows how to find the floor or to lay flat across the top of a lake. It just happens.
Billy, thanks for the correction! I was a bit absorbed in trying to decide whether it was a serious question that I got a bit sloppy. It would make windy days more interesting, non?
I want to be careful here because you seem to have an quantum background but I’m gonna go ahead and try not to get punked.
Hero first made the case for this fastest time thing, Fermat later came along and reworded it to something akin to what I have above.
Either Fermat, or someone else later massaged his thoeries into a more precise version that dealt with non-variances in optical path lengths being used to define the path, which isn’t exactly the fastest time theory but seemed close enough for this forum as I figured very few would understand what “non-variances in optical path lengths” means.
I seem however, to have underestimated the audience. My apologies.