Help me calculate log-paper value by hand

[StoppTidigare]

Hi, I got a problem, and my brain has stopped working. Wonder if somebody could help me:

If I have a log-paper where the distance between the values 1 and 10 is 4.5 cm. The value 3 is at 2.7 cm.
How can I calculate the value by hand if I don't want to rely on the marking ?

I want to have an formula that I can apply on an arbitrary measured distance on
a log-paper, and get the corresponding log value.

Kindest regards,
StoppTidigare

 

[Kral]

Re: log-paper problem

StoppTidigare,
Let Y = Value
d = distance from the "1" line
then
Y = 10^(d/4.5)
.
I believe you made an error in measurement. The distance for the value 3 would be 4.5 Log(3) = 2.147 from the "1" line.
.
Regards,
Kral

 

[neils_arm_strong]

log-paper problem

It would be 4.5*log. where n is the required value to which the length from 1 is to be calculated.