gear ratio problem

[jhpz3TCk]

so i have a questioe
I have done questions 1-3, but for 4 i do not understand how it is possible to solve this one if we are only given the minimum and maximum speeds and the calculation for the ratio.
Is there any way to calculate the second lower??

here is what i have

double M, m, r;

cout<<"Enter in the maximum speed in rpm (revolutions per minute): ";
cin>>M;

cout<<"Enter in the minimum speed in rpm (revolutions per minute): ";
cin>>m;

r=pow((M/m),(1/5.));

cout<<"The ratio between successive speeds of a six-speed gearbox is "<<r<<endl;

[Moschops]

Given two cogs, the first one with X teeth and the second with Y teeth, every time the first one goes round once, the second one will have gone round X/Y times.

So if the first one goes round at 350 rpm, the second one goes round at 350*(X/Y) rpm

[jhpz3TCk]

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[Moschops]

This is how gears work. Just knowing that two cogs are connected doesn't tell you anything about their relative rates of rotation. You need to either know about the teeth, or someone has to simply tell you that one will rotate at a given ratio of the other.

Are you missing something from the original question above? Here, where I've put XXX, did you mean to actually give us the ratio?

The ratio between successive speeds of a six-speed gearbox is XXX, where...

[Moschops]

I see the original poster has deleted his question. Not to worry, chums, here's the details as far as I can remember them:

The original question is from "Problem Solving, Abstraction, and Design Using C++" (Friedman, Koffman). Chapter 3, project 11, begins:

"The ratio between successive speeds of a six-speed gearbox (assuming that the gears are evenly spaced to allow for whole teeth) is

5(nth power) square root of (M/m)

where M is the maximum speed in revolutions per minute and m is the minimum speed. Write a function that calculates this ratio for any maximum and minimum speeds."

The original poster above wanted to know the speed of the second lowest gear, as I recall.

[webJose]

hehe, awesome, Moschops! That'll teach him/her. :D

[jhpz3TCk]

it is just

the ratio * the minimum speed to get the second lower.

so sl=r*m

that is what i was looking for, just what that equation was, simple now looking at it.