Could someone explain why the centripetal force and acceleration in this problem is facing out instead of in. PROBLEM ATTACHED

Question

happykiddo · Answer

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happykiddo · Answer

Is it because the curve is banked?

happykiddo · Answer

Is it because there is no friction force?

anonymous · Answer

I'm not really sure why it is in the opposite direction either. http://hyperphysics.phy-astr.gsu.edu/hbase/mechanics/carbank.html

happykiddo · Answer

Well that makes 2 then. No worries, I'll ask my professor next chance I get.

anonymous · Answer

Let me know! I'm intrigued

irishboy123 · Answer

the arrow represents the "magnitude" of the centripetal force

this is purposive and maybe a bit hand wavey😀.  the fact that the car "wants" to travel in a straight line means that it is bearing onto the curved wall. and that creates a reaction between the car and wall

as long as you get that, i really wouldn't be too bothered about words and names :p  

[a lotta people get hot under the collar about this centrifugal centripetal stuff and i really don't see the problem....as long as you understand what is physically happening.....]

anonymous · Answer

@IrishBoy123 I think he's asking why is the arrow pointing into the inclined plane, when it should actually be pointing away from the inclined plane (into the circle of motion).

If there's no friction, it could be that inertia wants the car to keep moving forward, so there's a consequent force outward. If there is friction, then the centripetal force is just the frictional force. Centripetal forces are fictitious forces -- there's no actual centripetal force that acts upon the car, it's more of a "category" of forces. Friction is one of the cases where it acts as a centripetal force, keeping the car along the circle (which is why it should point inward).

irishboy123 · Answer

who cares about the arrows?  the trick is in seeing the forces.  there will always be a reaction to every action.

but "Centripetal forces are fictitious forces"?!?!   don't get sucked in; that gets you absolutely nowhere  👀

anonymous · Answer

@IrishBoy123 Ahaha, many textbooks and professors would disagree with you; but I guess it is a strong topic of debate. Some say there is a real force and some say they aren't a real force. I was always taught by multiple professors that it's a "fake" force.

irishboy123 · Answer

that's philisophy :-)))