Understanding the Concepts

* Weight (W): The force of gravity acting on an object's mass. It's measured in Newtons (N).

* Mass (m): The amount of matter in an object. It's measured in kilograms (kg).

* Acceleration due to gravity (g): The acceleration experienced by objects falling freely near the Earth's surface. It's approximately 9.8 m/s².

Formula

The relationship between weight, mass, and acceleration due to gravity is:

Weight (W) = Mass (m) × Acceleration due to gravity (g)

Solving for Mass

1. Rearrange the formula to solve for mass:

m = W / g

2. Plug in the values:

m = 75 N / 9.8 m/s²

3. Calculate:

m ≈ 7.65 kg

Therefore, the mass of the rock is approximately 7.65 kilograms.