You can find weight if you know the mass of an object by using the formula: Weight = Mass × Acceleration due to gravity (W = mg).
Here's a more detailed explanation:
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Understanding the Concepts:
- Mass: Mass is a measure of the amount of matter in an object. It's a scalar quantity, meaning it only has magnitude (e.g., 5 kg).
- Weight: Weight is the force exerted on an object due to gravity. It's a vector quantity, meaning it has both magnitude and direction (e.g., 49 N downwards).
- Acceleration due to gravity (g): This is the acceleration experienced by objects due to the gravitational pull of a celestial body. On Earth, the standard value of 'g' is approximately 9.8 m/s². This value varies slightly depending on location and altitude.
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The Formula:
The formula W = mg is used to calculate weight.- W represents the weight of the object (measured in Newtons (N)).
- m represents the mass of the object (measured in kilograms (kg)).
- g represents the acceleration due to gravity (measured in meters per second squared (m/s²)). On Earth, g ≈ 9.8 m/s².
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Example:
Let's say you have an object with a mass of 10 kg. To find its weight on Earth:
Weight = Mass × Acceleration due to gravity
Weight = 10 kg × 9.8 m/s²
Weight = 98 NTherefore, the object weighs 98 Newtons on Earth.
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Important Considerations:
- The value of 'g' (acceleration due to gravity) changes depending on the celestial body. For example, the acceleration due to gravity on the Moon is approximately 1.625 m/s², which is much less than on Earth. Therefore, an object with the same mass will have a much lower weight on the Moon compared to Earth.
- Weight is a force, and it's measured in Newtons (N). Mass is a measure of the amount of matter, and it's measured in kilograms (kg). They are distinct but related concepts.
In summary, to find the weight of an object, multiply its mass by the acceleration due to gravity at its location.
