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Could someone explain to me why amplitude modulated radio stations transmit further distances in the evening? I have read somewhere that there is a change in the atmosphere that allows this at night time

My guess would be that there is no electromagnetic interferrence from the sun but i'm unsure of the specifics of how this really works.
Why doesn't it affect FM transmissions?

Cheers.

While Wikipedia is a great place for information the fact that it's editable by anyone means it's not reliable, experts and ameteurs alike can add their comments to an article and it's not always unbiased. While there are links to sources at the bottom of most articles it's usually cited as an unreliable resource.

Taking into account the above, how can you varify anything on the internet as a reliable resource? is Physorg.com reliable? how can you tell something has been peer reviewed or that the same information is generally accepted science? what about Howstuffworks.com too? I find that very informative but without a research background I find it difficult to tell.

When I post I'd like to be able to source reliable information in my posts but doing so online seems like a fallicious minefield.

So my neighbor has what I assume is HAM radio and a huge ariel outisde his house; I'm assuming HAM, could be Citizens Band but i don't know enough about it to tell the difference.

Anyway I use my computer rather regularly and all i can hear instead of what should be coming out of my speakers is really loud chatter from his signal. Its very annoying and so I was considering wrapping my speakers in aluminium kitchen foil to botch up a kind of faraday cage but i'm skeptial if this would help?

Any ideas? do you need more info?

Regards

Just browsing the internet for cool physicsy stuff i came accross this:



"New "Flying Train" prototype: Apart from aerodynamic drag, trains usually suffer from mechanical resistance in their drive system as well as rolling resistance from the wheels on the track. Researchers at the Kohama Laboratory, Institute of Fluid Science at the Tohoku University in Japan (link) tried to lower overall resistance by adapting another aspect of aerodynamics on its Aero-Train concept. Using the aerodynamic wing-in-ground (WIG) effect, the Aero-Train is able to fly above the track at a height of 10 centimetres (4 in).
The WIG effect occurs when flying very close to the surface. Cruising at its maximum speed of 500 kilometres per hour (310 mph), the aerodynamic lifting force becomes extremely large with a much smaller drag force.
Solar panels are placed on the guide-way's roof, while wind generators are placed alongside in those places where wind energy is generally available. The generated electricity can be fed to the train directly or stored in its on-board batteries. The researchers expect the system to generate much more energy than is consumed by the Aero-Train, thereby making it double as an electric power plant.
The next stage in the development is to build a larger Aero-Train prototype with room for six passengers and a maximum operating speed of 350 kilometres per hour (217 mph). The final, full-scale Aero-Train, with a length of 85 metres (279 ft) and seating capacity for 325 passengers, is aimed to begin service in 2020.


TECHNICAL SPECIFICATIONS:
DRIVE SYSTEM -- Ducted electric fans + WIG-effect
MAXIMUM SPEED -- 500 km/h (310 mph)
LENGTH -- 85 m (279 ft)
WIDTH -- 12 m (40 ft)
WEIGHT -- 70 tons (154,300 lbs)"

The part i've bolded I don't really understand and was hoping it could be explained to me. What i see is that it's somehow a magical perpetual motion device that powers it'self by moving and charging the wind generators; I could perhaps forgive the solar panels part but am I missing something?

Right, well...

Were all familiar with most films including this scenario involve some guy in a spaceship or whatever colliding into an asteroid or acidic blood from zenomorphs burning a hole in his ship. Suddenly WHOOOOSH! he's sucked out of a hole and thrown into the vacuum of space; and this is where my problem begins.

I'd been of the understanding that because space is empty that theres nothing there to "suck" with, it's really just the pressure within the spaceship "pushing" out and escaping to fill a lower pressure volume, right? If my line of thinking is correct it'd kinda support my second hypothesis of why a spaceship doesn't just get torn apart by the huge vacuum of space trying to get hold of all that atmosphere; Is it just that spaceships don't necessarily need to be that strong once in space (ignoring space debris and the chance of colliding with anything that is!) because the amount of atmosphere within the ship would never be enough to rupture it?

I think i know the answer but TL;DR atmosphere in the spaceship pushes outwards and is NOT sucked out by space?