Function recoil_velocity 

pub fn recoil_velocity(
    projectile_mass: f64,
    projectile_velocity: f64,
    body_mass: f64,
) -> Option<f64>

Computes recoil velocity assuming the initial total momentum is zero.

Uses v_recoil = -(projectile_mass * projectile_velocity) / body_mass.

Returns None when projectile_mass is negative, when body_mass is less than or equal to zero, when any input is not finite, or when the computed recoil velocity is not finite.

Examples

use use_momentum::recoil_velocity;

assert_eq!(recoil_velocity(1.0, 10.0, 5.0), Some(-2.0));