for (int i = 0; i < numObjects; i++)
{
float theta = i * 2 * Mathf.PI / numObjects;
float x = Mathf.Sin(theta)*radius;
float y = Mathf.Cos(theta)*radius;
GameObject ob = new GameObject();
ob.transform.parent = transform;
ob.transform.position = new Vector3(x, y, 0);
}