How do I find the mass of an object without k?

• swueettea
In summary, the displacement and the period for the two masses are not compatible. The spring constant for the 100g mass can be found using the information from the 100g mass.
swueettea
Homework Statement
determine the mass of the pink and blue objects by using Hooke's Law and by period.
Relevant Equations
T=2π( √m/k)
F=kx

time/#periods=T= 30.58/10= 3.058
Displacement=.6m
T=3.058

I tried to rearrange hooke's formula to k=f/x but f=mg and I don't have mass.
Using the period formula is also hard because T=2π( √m/k) and I have neither m or k :/

Attachments

• AP.PNG
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Do you have information about that yellow ##100g## mass?

swueettea
PeroK said:
Do you have information about that yellow ##100g## mass?
omg wait I didn't think about the 100g thank you. The displacement is 25cm(.25m) and F is 1N so the K=4N/m right? And that's the K I would use for the other masses?

swueettea said:
omg wait I didn't think about the 100g thank you. The displacement is 25cm(.25m) and F is 1N so the K=4N/m right? And that's the K I would use for the other masses?
The given displacement and period are not compatible. Is the displacement for the larger mass and the period for the smaller mass?

PeroK said:
The given displacement and period are not compatible. Is the displacement for the larger mass and the period for the smaller mass?
The period and the displacement in the post problem is for the pink object but wouldn't the spring constant I found for the 100g object work for all of them? the information I used to find the spring constant I got from the 100g object (the .25m and 1N).

swueettea said:
The period and the displacement in the post problem is for the pink object but wouldn't the spring constant I found for the 100g object work for all of them? the information I used to find the spring constant I got from the 100g object (the .25m and 1N).
It's not clear from the diagram what information you have. If you have either the displacement or the period for a known mass, then you can get the spring constant.

is this clearer?

But how could I find the spring constant with just the displacement or period if k=f/x and f=mg?

PeroK said:
It's not clear from the diagram what information you have. If you have either the displacement or the period for a known mass, then you can get the spring constant.
is this clearer?
View attachment 258807
But how could I find the spring constant with just the displacement or period if k=f/x and f=mg?

swueettea said:
is this clearer?
View attachment 258807
But how could I find the spring constant with just the displacement or period if k=f/x and f=mg?
Why can't you get the spring constant from the 100g mass?

PeroK said:
Why can't you get the spring constant from the 100g mass?
Then it'd be 4N/m since 1N/.25m=4N/m right? And I can use that for the pink and blue masses too? Sorry I thought you meant that it was wrong earlier when I had said it so I got really confused.

swueettea said:
Then it'd be 4N/m since 1N/.25m=4N/m right? And I can use that for the pink and blue masses too? Sorry I thought you meant that it was wrong earlier when I had said it so I got really confused.
I assume that's the idea.

swueettea
PeroK said:
I assume that's the idea.
Okay thank you so much for helping me!

1. How do I measure the mass of an object without using a scale?

One way to find the mass of an object without using a scale is by using the formula mass = density x volume. You can measure the volume of the object by submerging it in water and measuring the displacement of water. The density of the object can be found by researching the material it is made of.

2. Can I use a ruler to find the mass of an object?

No, a ruler cannot be used to find the mass of an object. A ruler measures length, not mass. To find the mass of an object, you will need to use a scale or another method such as the one mentioned in the first question.

3. How accurate is the method of finding mass without using a scale?

The accuracy of finding the mass of an object without using a scale depends on the accuracy of the measurements taken for volume and density. The more precise these measurements are, the more accurate the calculated mass will be.

4. Is it possible to find the mass of an object without any tools?

Yes, it is possible to find the mass of an object without any tools by using the method of estimating. This involves comparing the weight of the object to known objects of similar size and material. However, this method is not very accurate and should only be used as a last resort.

5. Can I find the mass of an object without knowing its density?

No, you cannot find the mass of an object without knowing its density. The formula mass = density x volume requires the density of the object to be known. Without this information, it is not possible to accurately calculate the mass of the object.

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