A solid ball is generally heavier than a soccer ball. This is due to the difference in their construction and materials. A solid ball, often made of metal or dense plastic, has a higher density and mass compared to a soccer ball, which is typically made of lightweight materials like leather and synthetic materials.

To provide a more detailed explanation, let's consider the specifications of both types of balls. A standard soccer ball, according to FIFA regulations, has a circumference of 68-70 cm and is filled with air. The weight of a regulation soccer ball is between 410 and 450 grams. On the other hand, a solid ball, especially if it is a metal ball, can weigh significantly more. For instance, a solid rubber ball might weigh around 500 grams, while a metal ball could weigh upwards of 1 kilogram or more.

The difference in weight is primarily due to the materials used. Solid balls are often made of metals such as steel or aluminum, which are much denser than the materials used in soccer balls. The density of a material is a measure of its mass per unit volume, and metals have a much higher density than the materials used in soccer balls, such as leather and synthetic materials.

Additionally, the construction of a solid ball contributes to its weight. A solid ball is typically solid throughout, meaning it has no air-filled cavity inside. This contrasts with a soccer ball, which has a hollow interior that is filled with air. The absence of a hollow cavity in a solid ball means that it has a higher mass for its size compared to a soccer ball.

In conclusion, a solid ball is heavier than a soccer ball due to the higher density and mass of the materials used in its construction, as well as the absence of a hollow cavity. This makes the solid ball a more substantial object overall.