# What is the radius of a round asteroid from which a person can develop the second cosmic speed, that is, jump into space and fly away?

What is the radius of a round asteroid from which a person can develop the second cosmic speed, that is, jump into space and fly away? We assume that a person on Earth jumps to a height of h = 1 m, the density of the asteroid is ρ = 2 g / cm3 we have a person who can put energy into a jump mgh = mV ^ 2/2, that is, develop a speed V = sqrt (2gh) = sqrt (2 * 10 * 1) = 4.5 m / s. This should be equal to the second space velocity for our asteroid.
The second cosmic = sqrt (2 * GM / R), where the mass of the asteroid is M = 4/3 * pi * R ^ 3 * ρ, we equate
2 * GM / R = 20
2 * G * 4/3 * pi * R ^ 2 * ρ = 20
R ^ 2 = 10 * 3 / (4 * 3.14 * ρ * G)
R = sqrt [10 * 3 / (4 * 3.14 * 2000 * 6.7 * 10 ^ -11)] = 10 ^ 5 * sqrt [3 / (4 * 3.14 * 20 * 6.7)] = 4200 meters Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.