Weight
A. Is always less than in magnitude than an object’s mass
B. Has the unit of kilos
C. Is a gravitational force
D. Is the same as mass
The correct answer and explanation is:
The correct answer is C. Is a gravitational force.
Weight is the force exerted on an object due to gravity. It is directly related to an object’s mass and the acceleration due to gravity, which on Earth is approximately 9.8 m/s². The formula to calculate weight is:
Weight=Mass×Acceleration due to gravity\text{Weight} = \text{Mass} \times \text{Acceleration due to gravity}
Mass refers to the amount of matter an object contains, and it is a scalar quantity, meaning it only has magnitude and no direction. Its unit is kilograms (kg), and mass is constant regardless of location. In contrast, weight depends on both the mass of the object and the local gravitational field. On Earth, gravity pulls objects towards the ground, creating the weight force.
For example, if an object has a mass of 10 kg, its weight on Earth would be:
Weight=10 kg×9.8 m/s2=98 N\text{Weight} = 10 \, \text{kg} \times 9.8 \, \text{m/s}^2 = 98 \, \text{N}
Here, the unit of weight is Newtons (N), not kilograms. Newton is the standard unit for force in the International System of Units (SI). This shows that weight and mass are related but not the same. While mass is the same everywhere (on the Moon, for example), the weight of the object will change depending on the local gravity. For instance, on the Moon, where gravity is about 1/6th of Earth’s gravity, the weight of the object would be much less, but the mass would remain the same.
In summary, weight is a force, measured in Newtons, and depends on both mass and gravity. It is not the same as mass, and it is always greater than mass in magnitude when measured on Earth because of the acceleration due to gravity.