How to check if my enemy hits the ground at a certain velocity then add explosive force.

Questions & Answers
1

Hello! Right now I am trying to make my first ever 2D game. I have an enemy who jumps in the air and when they fall they are supposed to cause a light explosive force to the player and also deal damage. The problem is that I do not know how to check if the enemy after jumping hits the floor at a certain velocity. I also do know how to add force to the player.

I tried using void onCollisions Enter2D but that calls it every time even if its moving.

    private void OnCollisionEnter2D(Collision2D collision)
    {
        if(collision.gameObject.tag == "Ground")
        {
            foreach (Collider2D Obj in Physics2D.OverlapCircleAll(transform.position, radius))
            {
                if (Obj.GetComponent<Rigidbody2D>() != null && Obj.gameObject != gameObject)
                {
                    Debug.Log("Calling Function");
                    Rigidbody2D rb = Obj.GetComponent<Rigidbody2D>();
                    ExplosionForce2D forceScript = GetComponent<ExplosionForce2D>();
                    forceScript.AddExplosionForce(rb, force, transform.position, radius);
                }
            }
        }
    }

ExplosionForce2D script: Pre-Made

public class ExplosionForce2D : MonoBehaviour
{
	public void AddExplosionForce (Rigidbody2D body, float expForce, Vector3 expPosition, float expRadius)
	{
		var dir = (body.transform.position - expPosition);
		float calc = 1 - (dir.magnitude / expRadius);
		if (calc <= 0) {
			calc = 0;		
		}

		body.AddForce (dir.normalized * expForce * calc);
	}


}
2

just add an if condicion comparing if the rb.velocity.magnitude is less or higher than your desired amount