Why are BART trains so loud?
Why are BART trains so loud? Like most trains, BART wheels are tied together with rigid axels and no differentials. This means the wheels always rotate at the same speed, even around corners. Because the inner radius is smaller, there is less distance to travel, which can cause a slippage between the wheels and track, which is noisy.
Why is the London Metro so loud?
According to Luis Gomez-Agustina, who teaches an acoustic course at London Southbank University, “the fact that most of the [London] Underground stations' surface materials are acoustically hard – [they are] highly reflective, they do not absorb sound – facilitates the noise generated to stay within the space for ...
What does Bart suffer from?
Skinner has Homer and Marge come to the school, and tells them Bart has attention deficit disorder (ADD). He will be expelled unless he takes a radical, untested, potentially dangerous new drug called Focusyn.
Does Bart ever go to jail?
Bart invites many people to his so-called wedding and plans to take all the unused gifts back for store credit, but he is stopped by Chief Wiggum, who arrests Bart and rejects his bribe of the wedding presents. Bart is sentenced to six months of juvenile detention by Judge Constance Harm.
How loud does BART get?
Why are BART trains so loud? Screeeeech, nothing sounds quite so piercing as a BART train zipping through the Transbay Tube. A few years ago, a Chronicle study found that the loudest stretches of track topped out at 100 decibels; 85 decibels is considered the threshold for potential hearing damage.
What would 170 decibels do to a human?
Sounds above 150 dB have the potential of causing life-threatening issues. Sounds between 170-200 dB are so intense that they can cause lethal issues like pulmonary embolisms, pulmonary contusions, or even burst lungs.
How does BART go underwater?
Built using the immersed tube technique, the Transbay tube was constructed on land in 57 sections, transported to the site, and then submerged and fastened to the bottom – primarily by packing its sides with sand and gravel. Opened in 1974, the tunnel was the final segment of the original BART system to open.
Is the BART faster than driving?
Berryessa/North San Jose to Embarcadero Station Taking BART, he noted, is also faster than driving the highly trafficked highways into San Francisco. “Being on BART makes me feel relieved. It's way more stressful driving,” he said.
Is BART train noisy?
BART actually has a big machine that grinds down the bumps on corrugated track, eliminating some of the noise. This explains why sometimes a portion of the BART system makes loud uuunnnhhh sounds one day and doesn't make a peep the next. You aren't crazy -- they just smoothed out the track at night.
Is it safe to BART at night?
Yes, but be watchful and mindful of your luggage. If someone seems sketchy or looks mentally unstable, then get up and move to another car.
Who did Bart get pregnant?
Bart becomes a savior to Springfield couples trying to conceive when he inadvertently uses voodoo to get his art teacher pregnant. Bart becomes a savior to Springfield couples trying to conceive when he inadvertently uses voodoo to get his art teacher pregnant.
Is BART more expensive than driving?
Taking the train has long been less expensive than driving when considering bridge tolls and parking — and now it's an even more affordable option when you consider most Bay Area gas stations are charging more than $6 a gallon.
What is the top speed of a BART train?
BART has 8 DMU train cars which each have a seating capacity of 104. 70 mph maximum; 35 mph average, including 20-second station stops. For BART to Antioch DMU trains, the maximum speed is 75 mph; 60 mph average.
Why is BART so squeaky?
But because of the design, one of the wheels ends up getting dragged against the rail on turns, which causes that high-pitched squeal. “So one wheel has to be sliding while the other is rolling,” Kolesar says.
How many decibels is a BART train?
Noise. Many BART passengers have noted that the system is noisy, with a 2010 survey by the San Francisco Chronicle measuring up to 100 decibels (comparable to the noise level of a jackhammer) in the Transbay Tube between San Francisco and Oakland, and still more than 90 decibels in 23 other locations.
Why are trains easier to hear at night?
At night, the air near the ground can have a different temperature than air only a few hundred feet above1. This affects the transmission of sound waves. There is usually less ambient noise after dark, so the distant train sounds louder. As pointed out elsewhere, maybe the trains don't use the horn in daytime.
Are the new BART trains quieter?
Testing has shown a drop of as many as 20 decibels in sound intensity. One way to think about the difference is if the decibel level of riding on a BART train with the old wheel profile and rail sounded like standing near a lawnmower the new system is more like being next to a dishwasher.
Why are trains louder at night?
The intensity of sound will vary at night, sometimes louder and sometimes softer. It has to do with the height and strength of a temperature inversion just above the ground. On clear, calm nights, it is cooler at the ground than higher up.