In the context of Newton's law of universal gravitation, what physical quantity is commonly described as the measure of the gravitational force acting on an object?

• A. Mass (the amount of matter in the object)
• B. Weight (the gravitational force on the object)
• C. Inertia (the object's resistance to changes in motion)
• D. Density (mass per unit volume of the object)

Answer: (B)

Verified step by step guidance

1. Understand that Newton's law of universal gravitation describes the force of attraction between two masses, which depends on their masses and the distance between them.
2. Recognize that the gravitational force acting on an object near the Earth's surface is commonly referred to as the object's weight.
3. Recall that weight is the force due to gravity and can be calculated using the formula \(\text{Weight} = m \times g\), where \(m\) is the mass of the object and \(g\) is the acceleration due to gravity.
4. Distinguish weight from mass: mass is the amount of matter in the object and is a scalar quantity, while weight is a force and a vector quantity.
5. Conclude that the physical quantity measuring the gravitational force acting on an object is its weight.