# Replacing speed with friction in formula

• Bob22314
So, one would need to quantify those things and find a mathematical equation or model to reflect that.Thanks for your input.In summary, the equation that shows TIME and FRICTION in a way that when Friction is increased, time will increase is not available.f

#### Bob22314

Hi, first of all sorry... I know (close to) absolutely nothing about physics except from what I remember from school a looong time ago... :-). So, my question might sound a bit silly here. But thanks a lot for taking you time already!

## Homework Statement

In retail business there is some discussion that we need to reduce "FRICTION" (which is meant to be anything that slows down a customer like waiting in line) because the modern customer has no "TIME". To illustrate that in a presentation I wanted to add an equation that shows TIME and FRICTION in a way that when Friction is increased, time will increase... hope that makes sense...

## Homework Equations

What equation shows TIME = xyzFRICTIONxyz?

## The Attempt at a Solution

1) TIME = DISTANCE/SPEED
2) Not sure how to replace SPEED with something that contains FRICTION. Tried some equations around FORCE, FRICTION and VELOCITY but got lost..

Thanks for your question. Generally, I mean in a simple case ##Friction = \mu \cdot F_N##. Where ##\mu## is a constant. And ##F_N## is the normal force, which is proportional to the weight of the costumer. Unfortunately friction is pretty much independent of time, and speed. What one can do is calculating the time one looses due tro friction.

Using perhaps ##F=m* \frac{d^2 s}{d^2 t} - F_f## Where ##F_f ## is the friction fource. So, higher friction, lesser force -> it takes longer time for a costumer to get from a to b.

## Homework Statement

In retail business there is some discussion that we need to reduce "FRICTION" (which is meant to be anything that slows down a customer like waiting in line) because the modern customer has no "TIME". To illustrate that in a presentation I wanted to add an equation that shows TIME and FRICTION in a way that when Friction is increased, time will increase... hope that makes sense...
Since you are using an idiosyncratic definition of "friction", the physics notion of friction is completely and utterly irrelevant. There is no physics content in the question.

As written, you have "friction" defined as "anything which slows down a customer". If you want to use this "friction" in an equation, you have to nail that definition down better. You have to make it quantitative. You need to be able to turn "a wad of gum on the ground around which the customer has to step and the fine print on the 10 items or less sign, causing some customers to reach for their bifocals" so that the result is a number like "an average of five seconds".

*voila*. Time = Friction.

Edit: You may want to check out https://en.wikipedia.org/wiki/Queueing_theory

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haruspex and Stephen Tashi
Consider the power needed to drag a box across a floor...

Power = friction force * velocity
Velocity = distance/time
So..
Power = friction force * distance/time

If power is limited and distance to be covered is fixed then as friction increases so does the time taken.

Thanks, Cwatters!

So if Power = FrictionForce * Distance/Time, then Time = (FrictionForce * Distance) / Power. Meaning if I keep everything else fix, then
b) reducing Power, increases time and finally

I can work with that very well! Thanks a lot! Sorry again for the rather un-physical physics-question... But you've been a great help. Great forum. Thanks.

Yes that all looks correct (for a box being dragged or pushed across the floor).

At the risk of confusing the situation... If we were talking about someone walking across a room (eg in a queue) then the "friction force" in the above equation isn't the friction between the man and the floor, rather it's anything that resists his motion (eg things like air resistance and friction in his joints, bending of shoes). Friction between the man and floor actually helps him walk rather than hinders him. Try walking on ice.

Thanks! I guess in this case it would indeed be something resisting his motion. Would that change the equation? Thanks again!

Thanks! I guess in this case it would indeed be something resisting his motion. Would that change the equation? Thanks again!
It is all pointless. There is no force and there is no motion. You appear to be attempting to apply physics concepts where they are not applicable, possibly in an attempt to conjure up scientific justification for some business practice.

+1

It wasnt my intention to imply those equations can be directly applied to the concept of friction in a retail/ sales setting. At best there is a similarity of terms.

In sales and marketing friction can mean anything that stops a customer making a decision to purchase. Such things aren't likely to be linear (removing half of the issues preventing a sale won't necessarily make a sale happen twice as fast).

*voila*. Time = Friction.
Well said... what concerns retailers is delay. Use of the term friction is just a pseudo-physical way of referring to it. An equation relating them merely expresses that usage and adds nothing.
A more useful contribution to the theory would be to say "stop calling it friction, it's delay".