Newtons does a 40 kg bag of stones weigh

In summary, a 40 kg bag of stones would weigh approximately 88 pounds on Earth, according to Newton's second law of motion which states that the weight of an object is directly proportional to its mass and the force of gravity acting upon it. This means that the weight of the bag would be different on other planets or in space, where the force of gravity is not the same as on Earth.
  • #1
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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  • #2
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
 
  • #3


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.
 

1. How do you calculate the weight of a 40 kg bag of stones in Newtons?

To calculate the weight in Newtons, you need to multiply the mass (40 kg) by the acceleration due to gravity (9.8 m/s²). The formula for weight is W = mg, where W is weight in Newtons, m is mass in kilograms, and g is acceleration due to gravity in meters per second squared. Therefore, a 40 kg bag of stones would weigh 392 Newtons (40 kg x 9.8 m/s²).

2. Is the weight of a 40 kg bag of stones different on different planets?

Yes, the weight of a 40 kg bag of stones would be different on different planets because the acceleration due to gravity varies on different planets. For example, on Mars, the acceleration due to gravity is about 3.7 m/s², so the weight of a 40 kg bag of stones would be about 148 Newtons (40 kg x 3.7 m/s²).

3. What is the difference between weight and mass?

Weight and mass are often used interchangeably, but they actually have different meanings. Mass is a measure of the amount of matter in an object, while weight is a measure of the force of gravity acting on an object. Mass is measured in kilograms, while weight is measured in Newtons.

4. Why do we use Newtons to measure weight?

We use Newtons to measure weight because it is the standard unit of force in the International System of Units (SI). It is derived from Newton's second law of motion, which states that force equals mass times acceleration. Using Newtons allows for a consistent and accurate way to measure weight, regardless of the location or gravitational pull.

5. Can the weight of a 40 kg bag of stones change?

Yes, the weight of a 40 kg bag of stones can change depending on its location and the gravitational pull. For example, if the bag of stones is taken to a location with a stronger gravitational pull, like the surface of a planet, its weight would increase. Similarly, if the bag of stones is taken to a location with a weaker gravitational pull, like in outer space, its weight would decrease.

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