What does gravitational field strength measure?

Gravitational field strength is defined as the force experienced by a unit mass placed in a gravitational field. It essentially quantifies how strong the gravitational force is at a particular location. The greater the gravitational field strength, the stronger the force acting on a mass within that field. This is typically measured in newtons per kilogram (N/kg).

In practical terms, if you were to place a 1-kilogram mass in a gravitational field with a gravitational field strength of 9.8 N/kg (such as near the Earth's surface), that mass would experience a gravitational force of 9.8 newtons. This direct relationship between force and mass within the context of gravity is a fundamental concept in physics, helping to describe the behavior of objects under gravitational influence.

The other options do not accurately describe what gravitational field strength measures. For instance, density refers to mass per unit volume, speed relates to how fast an object moves, and distance covered by an object falling is a different aspect of motion influenced by gravity rather than a measure of the gravitational field itself.