Pcm to multiplication factor
Type a value in pcm to get it in k instantly.
1.001k
That's about the same as a control rod step. That is about 0.15 dollars of reactivity.
Convert the other way: k to pcm
What it means
How far from critical?
Dollars use β = 0.0065 for uranium-235. A plutonium-fuelled or high-burnup core has a smaller β, so the same pcm is worth more dollars.
The math
How to convert pcm to k
The multiplication factor follows from the reactivity: k = 1 ÷ (1 − ρ) with ρ as a fraction. A dollar is one delayed neutron fraction, 650 pcm for uranium-235, and the period is about 8,470 ÷ pcm seconds.
Example: 100 pcm = 1.001 k.
Every unit
Your reactivity in every unit
Tables
pcm to k conversion table
| pcm | k |
|---|---|
| 1 pcm | 1.00001 k |
| 10 pcm | 1.0001 k |
| 50 pcm | 1.0005 k |
| 100 pcm | 1.001 k |
| 250 pcm | 1.00251 k |
| 500 pcm | 1.00503 k |
| 650 pcm | 1.00654 k |
| 1,000 pcm | 1.0101 k |
| 2,000 pcm | 1.02041 k |
| 5,000 pcm | 1.05263 k |
k to pcm conversion table
| k | pcm |
|---|---|
| 1.01 k | 990.099 pcm |
| 1.02 k | 1,960.78 pcm |
| 1.05 k | 4,761.9 pcm |
Quick answers
Quick answers
- How many k is 1 pcm?
- 1 pcm is 1.00001 k.
- How many k is 10 pcm?
- 10 pcm is 1.0001 k.
- How many k is 100 pcm?
- 100 pcm is 1.001 k.
The units
About these units
Pcm (pcm)
Per cent mille: hundred-thousandths of reactivity.
Multiplication factor (k)
How many neutrons each generation makes. Critical is exactly 1.
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