How to Calculate Schwarzschild Radius
What is Schwarzschild Radius?
Schwarzchild radius is event horizon size of non-rotating black hole. Objects inside cannot escape, even light.
Formula
Apply r_s = 2GM/c²
Step-by-Step Guide
- 1Input mass (solar masses or kg)
- 2Apply r_s = 2GM/c²
- 3Results show black hole horizon size
Worked Examples
Input
M = 10 solar masses
Result
r_s ≈ 30 km, density ≈10¹¹ kg/m³
Stellar-mass black hole
Common Mistakes to Avoid
- ✕Assuming black holes are absolute sinks (Hawking radiation evaporates)
- ✕Neglecting spin (rotating black holes larger)
Frequently Asked Questions
What happens at event horizon?
Tidal forces increase dramatically; approaching observer experiences infinite time dilation.
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