Re: [Phys-l] Accelerating automobile

[Brian Whatcott <betwys1@sbcglobal.net>]

At 05:02 PM 1/5/2008, you wrote:
> My department just switched to the latest version of Serway - 
> Physics for Scientists and Engineers. The following problem is 
> presented in chapter 5 (prob 26):
>
> "A car is moving forward slowly and is speeding up. A student claims 
> "the car exerts a force on itslf" or "the car's engine exerts a 
> force on the car" Argue that this idea cannot be accurate and that 
> friction exerted by the road is the propulsive force on the car."
>
> How would members of this list respond to this problem? If I am 
> standing on ice and push off from a rigid wall, is it the wall 
> providing the propulsive force on my torso or is it the muscles in my arm?
>
> Bob at PC

I expect that Serway wanted one to offer that the car provides a force
 on the road, and ultimately on the Earth, and in turn, the road returns
 with a force on the car, given that traction is not eliminated by ice.


Brian Whatcott    Altus OK    Eureka!