The discussion revolves around calculating average velocity from a bike ride and understanding the implications of acceleration in a physics context. The original poster presents a scenario involving two segments of a bike ride and seeks to determine the average velocity. Additionally, there is a subsequent question regarding the safe stopping distance for a car hitting a barrier, incorporating concepts of acceleration and initial velocity.
The discussion is active, with participants providing insights and corrections to each other's reasoning. There is a mix of attempts to clarify concepts and calculations, with some participants questioning assumptions and definitions related to acceleration and velocity.
Participants are working under the constraints of homework rules, which may limit the depth of guidance provided. There is an emphasis on understanding the relationships between distance, time, velocity, and acceleration without providing direct solutions.
chroot said:What does it mean when we say an acceleration is, for example, "300 meters per second per second?"
It means that for each second an object is subjected to that acceleration, it will experience a change in velocity of 300 meters per second.
If your car starts out going 110 km/hr, which is just about 30.5 m/s, and is subjected to an acceleration of -300 m/s^2, then it will take just about a tenth of a second for the car to come to a stop. (In an entire second, the car would lose 300 m/s of velocity; every tenth of a second, the car will lose one tenth of 300 m/s of velocity.)
- Warren
In one second, the car loses 300 m/s of velocity. That's an acceleration of -300 meters per second, per second.It means that for each second an object is subjected to that acceleration, it will experience a change in velocity of 300 meters per second.