Lorentz factor to kinetic energy
Type a value in γ to get it in × mc² instantly.
1.29× mc²
That's about the same as 90% of light speed. A year aboard would be about 2.29 years back home.
What it means
How relativistic is that?
These are the effects for steady motion in a straight line. Acceleration and gravity add their own, which is general relativity rather than special.
The math
How to convert γ to × mc²
The Lorentz factor is γ = 1 ÷ √(1 − v²/c²), and back again v = c × √(1 − 1/γ²). Time dilation is γ, length contraction is 1/γ, and the kinetic energy is (γ − 1) times mc².
Example: 2.29 γ = 1.29 × mc².
Every unit
Your speed in every unit
Tables
γ to × mc² conversion table
| γ | × mc² |
|---|---|
| 1.01 γ | 0.01 × mc² |
| 1.05 γ | 0.05 × mc² |
| 1.15 γ | 0.15 × mc² |
| 1.25 γ | 0.25 × mc² |
| 1.67 γ | 0.67 × mc² |
| 2.29 γ | 1.29 × mc² |
| 3.2 γ | 2.2 × mc² |
| 7.09 γ | 6.09 × mc² |
| 22.4 γ | 21.4 × mc² |
× mc² to γ conversion table
| × mc² | γ |
|---|---|
| 0.01 × mc² | 1.01 γ |
| 0.1 × mc² | 1.1 γ |
| 0.3 × mc² | 1.3 γ |
| 0.5 × mc² | 1.5 γ |
| 0.6 × mc² | 1.6 γ |
| 0.8 × mc² | 1.8 γ |
| 0.9 × mc² | 1.9 γ |
| 0.95 × mc² | 1.95 γ |
| 0.99 × mc² | 1.99 γ |
| 0.999 × mc² | 1.999 γ |
Quick answers
Quick answers
- How many × mc² is 1 γ?
- 1 γ is 0 × mc².
- How many × mc² is 10 γ?
- 10 γ is 9 × mc².
- How many × mc² is 2.29 γ?
- 2.29 γ is 1.29 × mc².
The units
About these units
Lorentz factor (γ)
The number everything in special relativity scales by.
Kinetic energy (× mc²)
The energy it takes to get there, in multiples of the rest energy.
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