How to weigh an object that's heavier than the max. weight of the spring scale

[krosenberg]

Homework Statement

suppose that a spring is used in a spring scale that is limited to a maximum value of 25N, but you would like to weigh an object of mass M that weighs more than 25N.
What commonly available equipment, along with the spring scale, can be used to determine the weight of the object without breaking the scale?

The Attempt at a Solution

I have a feeling that attaching another spring to the scale would work, but I don't know how to explain why, and how i would then determine the weight of the >25N object.

Any suggestions?

 

[mgb_phys]

Depends how you were planing to attach the other scale.
Forget scales for a moment and imagine you had a rope with a breaking strain of 1Ton and you needed to lift 1.5T, does it become obvious how to attach two ropes? How much force would be on each rope ?
How does this translate to the scales?

Another approach would be to build a balance with another 25N weight - then arrannge it so the scale only measures the difference. This is actually how high precision balances work.

 

[ogb p]

There are a few options for weighing an object that is heavier than the maximum weight of a spring scale. One option is to use multiple springs connected in series to increase the overall maximum weight capacity of the scale. This is similar to your initial suggestion, but it is important to note that the springs must be of the same type and have the same spring constant to ensure accurate measurements. The weight of the object can then be determined by adding the readings from each spring together.

Another option is to use a lever system, such as a balance or a triple-beam scale, in conjunction with the spring scale. The object can be placed on one side of the lever and a known weight can be placed on the other side until the lever is balanced. The weight of the object can then be calculated based on the known weight and the distance from the fulcrum.

Alternatively, you could use a digital scale or a bathroom scale to measure the weight of the object. These types of scales typically have a higher weight capacity than spring scales and can provide an accurate measurement.

It is important to note that when using any of these methods, it is crucial to calibrate the equipment and ensure that it is functioning properly to obtain accurate measurements. Additionally, it is important to consider the precision and accuracy of the equipment being used, as this may affect the accuracy of the final measurement.