If your windows are plagued with stubborn grease stains or fingerprints, rubbing alcohol is an ingredient you should consider adding to your DIY window cleaner recipe. However, rotary lawnmowers that use electric motors powered by a cord, a rechargeable battery or even solar power are also popular. Like chain saws, many lawn trimmers use an oil-and-gas mixture that sends pollutants into the air. The important part of this process is that air molecules propagated the sound wave from its source to your ear. Sound is an example of a longitudinal wave. One example of the correct depiction of the lack of sound in space is Stanley Kubrick’s classic film, “2001: a Space Odyssey.” We see shots of the inside of spacecraft (Discovery, pods, moon vehicles) with sounds of machinery and alarms. In Star Trek and Star Wars, spacecraft often accelerate from rest or sub-light speed to light speed or more in a matter of seconds. The crews of these spacecraft would experience huge forces of acceleration (G-forces), even more than the G-forces experienced by jet fighter pilots when they accelerate and maneuver their aircraft. To compensate for this, Star Trek writers came up with the idea of inertial dampers, which counteract the forces of acceleration.

In “Star Trek,” the Enterprise fires its phasers at enemy space ships. In “The Physics of Star Trek,” Lawrence Krauss speculates how these devices might work, but to date no such device exists. In both “Star Wars” and “Star Trek,” people fire hand-held laser or phaser weapons. When the rebel forces destroy the Death Star in “Star Wars Episodes IV” and “VI,” each Death Star goes out with a loud explosion. The gravitational forces inside would rip any matter apart. The core of the collapsed star becomes so dense and the gravitational forces so great that nothing, not even light, can escape. They will attract objects by virtue of their mass and gravity just as the star that bore them did (remember that the black hole has the same mass as the star, just more compact, or dense). A black hole is not a tunnel. So, the Earth would experience the same gravitational attraction to the Sun if it became a black hole as it does now. Any object that enters the edge or event horizon of the black hole falls into it.

F is the force, m is the mass of the object and a is the acceleration. An object that gets within the distortion of space caused by a large mass (like a gravity well) gets attracted to that mass. Einstein revised Newton’s theory and envisioned gravity as a distortion of space caused by mass. Einstein’s theory explained everything that Newton’s did and more (the odd behavior of Mercury’s orbit, the bending of light by gravity). But if you examine Newton’s law of gravity above, neither the mass of the Sun nor the Earth changes, and neither does the distance between them. If the Sun were to instantly become a black hole, many people think that it would suck the Earth into it (Although the Sun does not have enough mass to become a black hole). A knotted cord: The cord has to be longer than your drinking tube and the knot should be large enough to fit snugly inside it.

Most dramatically, there is a scene where astronaut David Bowman must get inside the spaceship Discovery from a space pod without his helmet. He decides to decompress his space pod exposively to propel himself into an open airlock aboard the space ship Discovery. The films “2001: a Space Odyssey, ” “2010: The Year We Make Contact,” and “Mission to Mars” all depict this type of artificial gravity correctly. Such explosions happen in many sci-fi movies and TV series, such as when “Star Trek”‘s Enterprise destroys an enemy vessel, or when the Nostromo self-destructs in “Alien.” The problem here is that sound does not carry in space. A black hole is caused by the collapse of a star at the end of its life (The star must be at least three times more massive than the Sun). The producers of the most favorite aluminum boat cleaner are STAR BRITE, Aluminum Brightener, 3M Marine, MaryKate Aluminex, Toon-Brite, Sharkhide, Aluma Bright, JJV’s Best, Aluminox, Duragloss 552, Bio-Kleen, Alumi Brite, and TotalBoat.