Many planets in our solar system (Saturn,Uranus,Neptune) have rings. If these rings are made of chunks of debris, why do they form around the planet and not travel toward the sun

Answer 1

Generally, rings form from moons, asteroids, or comets that have disintegrated due to a collision or because they got too close to their planet (Roche Limit). Some of the debris will have enough energy to escape from the planet's gravity and will then travel toward the sun. Most of the debris, however, will not have enough energy to overcome the planet's gravity and will remain in orbit around the planet.