- #1
vxr
- 25
- 2
- Homework Statement
- Why car decelerates after releasing the gas pedal?
- Relevant Equations
- none
After the foot is released from the gas pedal, the car will naturally start decelerating.
From my understanding two things are causing this: air resistance and kinetic friction. From my understanding also, in a vacuum and in a place where gravity is relatively small, the car would not decelerate at all. (putting aside the fact that it probably wouldn't be able to drive forward on a surface at all, I guess)
But can someone give a more detailed explanation?
Two questions mainly:
1. Why exactly air resistance is causing deceleration, or for example due to air resistance free falling object has some critical (maximum) velocity. But why is air doing that? Is it because, well, air is basically bunch of gas atoms that are colliding with a moving object, creating some Force?
2. Why is kinetic friction of tires causing deceleration? From my understanding it's mainly due to force of gravitation, and without gravitation there most likely wouldn't be friction, because there would be no contact force (caused by weight) and no ground reaction force (3rd Newton Law I believe).
I just need some "more formal" explanation on both of my questions. Thank you.
From my understanding two things are causing this: air resistance and kinetic friction. From my understanding also, in a vacuum and in a place where gravity is relatively small, the car would not decelerate at all. (putting aside the fact that it probably wouldn't be able to drive forward on a surface at all, I guess)
But can someone give a more detailed explanation?
Two questions mainly:
1. Why exactly air resistance is causing deceleration, or for example due to air resistance free falling object has some critical (maximum) velocity. But why is air doing that? Is it because, well, air is basically bunch of gas atoms that are colliding with a moving object, creating some Force?
2. Why is kinetic friction of tires causing deceleration? From my understanding it's mainly due to force of gravitation, and without gravitation there most likely wouldn't be friction, because there would be no contact force (caused by weight) and no ground reaction force (3rd Newton Law I believe).
I just need some "more formal" explanation on both of my questions. Thank you.