Jindra can't find a girlfriend, so he orders a female-attracting device from a dubious online store. He received a pocket black hole. At a distance of 5 m, the black hole exerts gravitational acceleration of 9.81 m·s⁻² on all bodies (including girls). Calculate the Schwarzschild radius of this black hole.
Jindra thought about complaining, but the black hole swallowed him.