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I have a German engineering thesis written in 1963 from Technische Hochschule Hannover.

In the results the author displays stress with the units of kp/cm² and the load as Mp. I am assuming the “p” is for Pfund which I am finding equal to 500 grams.

However, when I convert this to modern units of MPa and Newtons the results are too large to make sense. The results are about twenty times higher than what I expect:

1 kp/cm² ≙ (1 kp/cm²) · (500 g/p) · (9.81 N/kg) · (100 cm/m)² = 49,050,000 N/m² = 49.05 MPa

1 Mp ≙ (1 Mp) · (500 g/p) · (9.81 N/kg) = 4,905 kN

Could kp and Mp mean something else than Kilopfund and Megapfund?

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Andrew
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    I'm voting to close this question as off-topic because this is not a question about an aspect of German language. This is a question about units in technic and physics. – Hubert Schölnast Oct 20 '15 at 17:07
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    @Hubert Schölnast: Hmm, but there are language-specific differences; e.g., in French it was called kilogramme-poids (or kilogramme-force) and abbreviated in a different way. If the question were to be closed, though, I’d think “general reference” would be a better reason (WP de, WP en, even WP fr). Anyway, voted to leave open. – chirlu Oct 20 '15 at 18:03
  • Pfund would be abbreviated to Pfd. or as WIkipedia states (but I don't remember ever having seen it) to Pf, in both cases with a capital P. – guidot Oct 20 '15 at 19:50
  • Pfund ist generell in der Wissenschaft nicht verwendet worden, nur an Lebensmitteltheken, zumindest nicht seit Einführung metrischer Maße vor mehr als 100 Jahren. – user unknown Mar 17 '16 at 13:35

1 Answers1

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That's a now deprecated unit:

Kilopond, (abbreviated "kp", the English term: kilogramm-force), that measured the force via gravitational acceleration of an object with a mass of one kg in standard gravity.

Expressed in modern SI units it is equal to 9.80665 N.

Mp is Megapond, 1000 kp

Matthias
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    As the German Wikipedia article says, In Germany the Kilopond has been replaced by the Newton in 1978. I passed my Abitur in 1980, and can remember the kp being used in schoolbooks, probably until 1977, or maybe one or two years before. – Walter Tross Oct 20 '15 at 19:29