**Correct Option: A. Mass is a measure of the amount of matter in an object, while weight is the force exerted by gravity on that object.** ### Detailed Explanation: 1. **Understanding Mass:** - Mass is a fundamental property of matter. It quantifies the amount of matter contained in an object and is usually measured in kilograms (kg) or grams (g). - Mass is an intrinsic property, meaning it does not change regardless of the object's location in the universe. For example, a 1 kg object has a mass of 1 kg whether it is on Earth, the Moon, or in space. 2. **Understanding Weight:** - Weight, on the other hand, is the force exerted on an object due to gravity. It is calculated using the formula: \[ W = m \cdot g \] where \( W \) is weight, \( m \) is mass, and \( g \) is the acceleration due to gravity (approximately \( 9.81 \, \text{m/s}^2 \) on Earth). - Weight is a vector quantity, meaning it has both magnitude and direction (toward the center of the gravitational body). Weight is measured in Newtons (N). 3. **Key Differences:** - **Nature of Measurement:** Mass measures the amount of matter, while weight measures the gravitational force acting on that matter. - **Dependence on Gravity:** Mass remains constant regardless of location, while weight varies depending on the strength of the gravitational field. For instance, an object weighs less on the Moon than on Earth due to the Moon's weaker gravitational pull. ### Why Other Options Are Incorrect: - **Option B:** "Mass is dependent on the location of the object, while weight remains constant regardless of location." - This statement is incorrect because mass does not depend on location; it remains constant. Weight, however, does change with location due to variations in gravitational acceleration. - **Option C:** "Mass can be measured in Newtons, while weight is measured in kilograms." - This is incorrect because mass is measured in kilograms (kg), while weight is measured in Newtons (N). This option confuses the units of measurement for mass and weight. - **Option D:** "Mass changes with changes in temperature, while weight does not." - This statement is misleading. Mass does not change with temperature under normal conditions. While the volume of some materials may change with temperature (leading to changes in density), the mass itself remains constant. Weight can change with temperature indirectly if the gravitational field changes, but this is not a direct effect of temperature. ### Common Pitfalls: - Confusing mass and weight is a common mistake. Remember that mass is a measure of matter, while weight is a force due to gravity. - Forgetting the units: Always remember that mass is in kilograms and weight is in Newtons. - Not considering the effect of gravity when discussing weight, especially in different gravitational fields (like on different planets). ### Revision Summary: - Mass is the amount of matter in an object; it is constant and measured in kilograms. - Weight is the force of gravity on an object; it varies with location and is measured in Newtons. - Use the formula \( W = m \cdot g \) to calculate weight, where \( g \) changes based on the gravitational field. - Remember the distinction in units: mass (kg) vs. weight (N).