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Breaking and Bending of Spaghetti Lab

Introduction:

Spaghetti is dry pasta that has chemical and physical properties. It has been investigated in physics

many times to understand its breaking and bending.

When we hold many spaghetti noodles together and try to break them, we find it difficult. But if we

break one noodle, we find it easy. One noodle doesn’t need as much force to break as many noodles

held together. Now, what about the distance between these noodles, does it have any effect on the

force needed to break them?

The force will be in form of masses hanged to the spaghetti noodles.

Research question:

How does the distance between three spaghetti noodles affect it’s the mass needed to break them?

Apparatus:

Spaghetti

Thread

Tape

Masses of 10g

Two thick sticks

Four clumps

Method:

Set up the apparatus shown in the pictures below:

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Put three spaghetti noodles next to each other with no separation.

Stick them to the thick stick using a tape.

Tie a thread around the noodles.

Hang a mass of 10g to the thread.

Keep adding masses until all noodles break and the masses fall down.

Record the mass needed to break the noodles.

Repeat the same steps for three other noodles put apart by 1 cm, 2cm, 3cm and 4cm each

time.

Research Question:

How does the mass needed to break three spaghetti noodles depend on the distance between the

noodles?

Variables:

1. Independent variable: the distance between the three noodles. Each time I will change the

distance between the noodles and see what is the mass needed to break all of them. The

distances were measured by a ruler.

2. Dependent variable: the mass needed to break the three noodles tied together. I will hang a

clump to the thread that ties the noodles, and each time I will add 10g and record at what

mass all the noodles break.

3. Controlled variable: ‘

The same type of spaghetti: I have noticed that spaghetti have many types and

different thicknesses. The substances used to make spaghetti noodles differ so that

may affect the breaking strength of spaghetti and consequently affect the results.

Therefore, only one type of spaghetti is used throughout the experiment.

The height of spaghetti noodles: I made sure to choose noodles of the same height so

that the volume of spaghetti will not have a negative effect on the results.

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The experiment was repeated 5 times for each of 5 different distances ranging from 0cm to 4cm.

The masses clumps wasn’t large enough to hanged to the noodles which are apart by 3 and 4cm so I

decided to attach a tied thread around the three noodles and then attach the mass clump to it.

The time taken to break the spaghetti was ignored in this experiment since I am only concerned in

the relationship between mass and the distance between noodles.

Hypothesis:

When spaghetti noodles are tied together, their breaking is hard since their joining point is in the

middle and acts against the mass and the noodles are bended only in one direction downwards.

I expect that when the distance between noodles increases, the mass needed to break them

decreases. Because it will be harder for the noodles to reach the joining point and they will be bend

in two directions downwards and sideways.

Data collection and processing:

Raw Data:

Below is the table from the 5 trials performed for each of 5 different distances between spaghetti

noodles.

The uncertainty in distance is estimated to be ±0.002m because the distance between noodles was

small easy to measure and control using tape.

Uncertainty in mass was initially estimated to be ±10g because in each trial I added a mass of 10g.

Then, I calculated the uncertainty using the equation:

(𝑀𝑎𝑥 𝑀𝑎𝑠𝑠 − 𝑀𝑖𝑛 𝑀𝑎𝑠𝑠)

2

The percentage uncertainty is calculated using the equation:

(𝑈𝑛𝑐𝑒𝑟𝑡𝑎𝑖𝑛𝑡𝑦 × 100)

𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝑚𝑎𝑠𝑠

Since the calculated uncertainty is more significant than the estimated uncertainty, it will be

Distance

/m

±0.002m

Trial 1

/g

±10

Trial 2

/g

±10

Trial 3

/g

±10

Trial 4

/g

±10

Trial 5

/g

±10

Average

/g

±10

Max

/g

±10

Min

/g

±10

Uncertainty

/g

Percentage

Uncertainty

/%g

0.000 310 340 340 370 350 342 370 310 30 9

0.010 250 280 260 260 300 270 300 250 30 9

0.020 210 210 220 230 210 216 230 210 10 5

0.030 170 160 160 180 190 172 190 160 20 9

0.040 160 170 170 170 150 164 170 150 10 6

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considered, and the estimated uncertainty will be ignored.

The mass was taking after the all spaghetti noodles break and the masses fall down.

Processed Data:

I plotted the average mass against the distance between noodles and got this graph:

The graph shows that there is an inverse relationship between mass and distance.

In order to get a straight line that shows a linear relationship between the separation of the noodles

and the mass needed to break them, I will calculated the inverse of mass and then, plot it against

distance.

The percentage uncertainty in inverse mass is the same as percentage in average mass.

The uncertainty of inverse mass is then calculated using the equation:

(𝑃𝑒𝑟𝑐𝑒𝑛𝑡𝑎𝑔𝑒 𝑈𝑛𝑐𝑒𝑟𝑡𝑎𝑖𝑛𝑡𝑦 × 𝐼𝑛𝑣𝑒𝑟𝑠𝑒 𝑀𝑎𝑠𝑠)

100

The results are shown in the table below:

Distance

/m

±0.002m

Mass

Inverse

/g-1

Uncertainty

/g-1

0.000 0.0029 0.0003

0.010 0.0037 0.0003

0.020 0.0046 0.0002

0.030 0.0058 0.0005

0.040 0.0061 0.0004

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After plotting inverse mass against distance, I got this graph:

The gradient of the graph is: 0.085g-1m-1

The maximum gradient is: 0.097 g-1m-1

The minimum gradient is: 0.063 g-1m-1

The uncertainty is gradient can be calculated from

(max gradient – min gradient)

2=

0.097 − 0.063

2= 0.02

The slope of graph is 0.09g−1m−1 ± 0.02 g−1m−1

Concluding and evaluating:

After performing the experiment and analysing the results, I found that the results supported the

hypothesis, as the distance between the noodles of spaghetti increases, the mass needed to break

them decreases.

After plotting the inverse of mass against the distance, I got a straight line that shows a linear

relationship between the inverse of mass and the separation of spaghetti noodles.

This relationship can be described by the equation:

𝑦 = 𝑎𝑥 + 𝑏 Where 𝑎 and 𝑏 are constants.

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𝑚 = 𝑎 𝑑 + 𝑏 Where m is the mass and d is the separation between spaghetti noodles.

So the relation between the mass and the separation between noodles can be given by the equation:

𝟏

𝒎= 𝟎.𝟎𝟖𝟓𝒅 + 𝟎.𝟎𝟎𝟑

Evaluation and conclusion:

The experiment in general was well controlled and gave me sufficient results that show a

relationship between mass and distance. There were some trials which weren’t well controlled and

cause to have inaccurate results, for instance the fourth point on the graph was a bit higher and out

of the best fit.

Weaknesses Effect Improvement

The thread used to tie the

noodles wasn’t changed throughout the experiment.

The thread might be starched

and gained internal energy and acted against the force of the masses.

Cut many thread of equal

height and change the thread used after each trial.

The range investigated is

limited.

Not getting enough data to

know the exact relationship between distance and mass.

Extend the range of distances

investigated.

The masses available are of

minimum 10g.

Large uncertainties. Get masses of small units.