Newtons does a 40 kg bag of stones weigh

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A 40 kg bag of stones weighs approximately 392 Newtons when calculated using Earth's gravitational acceleration of 9.8 m/s². The formula for weight is F = ma, where F is the force in Newtons, m is mass in kilograms, and a is acceleration due to gravity. The initial claim of 302 Newtons is incorrect, likely due to a typographical error. The correct calculation shows that the weight is 40 kg multiplied by 9.8 m/s². Therefore, the weight of the bag of stones is confirmed to be 392 Newtons.
espo
how much in Newtons does a 40 kg bag of stones weigh? my answer is 302 Newtons is that correct?
 
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Hi espo,

Just think about Newton's second law,

F = ma

If you have a bag of stones with a mass of 40 kg, and that bag of stones is in Earth's gravitational field (and thus has an acceleration of 9.8 m/s), then it must exert a force of 40 * 9.8 Newtons on the ground. This force is what we call weight.

The bag weighs 40 * 9.8 = 392 N. Perhaps you typed 302 accidentally, when you meant to say 392?

- Warren
 


Yes, your answer of 302 Newtons is correct. This is because the weight of an object in Newtons is equal to its mass in kilograms multiplied by the gravitational acceleration of 9.8 meters per second squared. Therefore, a 40 kg bag of stones would weigh 40 kg x 9.8 m/s^2 = 392 Newtons. However, since the question specifies a 40 kg bag of stones, it is likely referring to an object on Earth, where the gravitational acceleration is typically rounded to 9.8 m/s^2. Therefore, the weight in Newtons would be approximately 40 kg x 9.8 m/s^2 = 392 Newtons.
 

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