1. (Units) a unit of heat in the fps system equal to the quantity of heat required to raise the temperature of 1 pound of water by 1Â°F. 1 British thermal unit is equivalent to 1055.06 joules or 251.997 calories.
Quick Answer. A major factor that usually causes tire noise is the air chamber inside the tire. The large void that is filled with air acts as a giant resonance chamber. Thus, the tires are something like donut-shaped drums that generate a low-frequency hum when tires are rolling.
While I'm driving, there is a thump thump thump noise coming from a wheel that is in rhythm with the tire rotation. Faster you accelerate, the faster the noise. You can only hear it when driving 20mph or higher. No grinding noise, though. I cannot hear it as well... show more I have an '03 Toyota Camry with 83k miles.