Why Do I Get Negative Values Solving the SHM Spring Problem?

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Negative values were encountered when solving the SHM spring problem due to confusion over the parameters used in the equations. The time period of 0.8 seconds is specifically for mass m1 alone, while the displacement of 0.38 meters needs clarification on whether it applies to both masses or just the 50g mass. Proper calculations indicate that significant figures should be limited to match the data provided, suggesting results of 1.3 kg/s² for the spring constant k and 0.021 kg for m1. The discussion highlights the importance of clarity in variable definitions and unit consistency in physics problems. Accurate interpretation of the problem is essential to avoid erroneous results.
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Homework Statement
A block of unknown mass is attached to the end of a vertical spring. When a second 50 g block is suspended, the spring extends by 38 cm. The oscillation period without the second 50 g block is 0.8 s. Find:

(a) the spring constant of the spring (in N/m);
(b) the mass of the first block (in kg).
Relevant Equations
T=2pi*sqrt(m/k)
k=mg/x
m1 = unknown
m2 = 0.05 kg
x = 0.38 m
T = 0.8s

Tried to plug in values into the above equations:

0.8 = 2pi*sqrt(m1+0.05/k)
k = ((m1+0.05)*9.8)/0.38

Got negative values for both k and m which doesn't make sense
 
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torinketo said:
0.8 = 2pi*sqrt(m1+0.05/k)
The 0.8 seconds is for m1 by itself.
torinketo said:
k = ((m1+0.05)*9.8)/0.38
It's not clear whether the 0.38m is for the masses together or just the 50g mass.
 
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haruspex said:
The 0.8 seconds is for m1 by itself.

It's not clear whether the 0.38m is for the masses together or just the 50g mass.
Thank you very much, this was the right answer :)

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torinketo said:
Thank you very much, this was the right answer :)

View attachment 338824
Good, but you show too many significant figures. The data you were given only have two (the 0.8s only one, but probably intends 0.80s). And you should always state the units. So better answers are 1.3 kg/s2 and 0.021kg.
 
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