Very very noob calculation verification [BEDMAS]

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seto6
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Homework Statement



Handwritten-style worked calculation of a Lorentz transformation for a lightning strike at x = 30 km and t = 10 μs, giving x' = 32.91 m ≈ 33 m and t' ≈ -46.2 μs ≈ -46 μs.



The Attempt at a Solution


i calculated and got like

x'=3.291*104 ---->this does not match with answer key, but I am sure its correct.
could some one verify this pls

t'=-4.618*10-5---. this makes sense
 
It can't be correct, it doesn't have the right units.

What calculation did you do? Show your work...
 
i did the exact thing as the solution, i think they converted the x'=32917.5m to x'=32.9km and did not indicate it...
 
x' should be less than x. t' should be greater than t. Also a negative time interval doesn't make sense.
 
Last edited:
seto6 said:
i did the exact thing as the solution, i think they converted the x'=32917.5m to x'=32.9km and did not indicate it...
They're the same thing (except for rounding), it's not necessary to indicate anything for that conversion.

And a negative time interval could make sense, if it's the time difference from A to B and B happened before A.

Anyway, I still don't see your work. Unless the image you show is actually the work you did? I thought it was the given solution.
 
Aha: I just checked the calculations in the image you showed. I can't say whether the calculation is set up correctly, but there is definitely an error. When I plug
[tex](1.155)\bigl[3.0\times 10^4\,\mathrm{m} - (0.5)(3.0\times 10^8\tfrac{\mathrm{m}}{\mathrm{s}})(1.0\times 10^{-5}\,\mathrm{s})\bigr][/tex]
into my calculator, I get [itex]32.9\,\mathrm{km}[/itex]. So the result shown in the image is off by a factor of 1000 - probably whoever did that calculation wrote the wrong units on the result.
 
its from a solution Manuel. I am 100% sure its wrong off by a factor of 1000
 
diazona said:
Anyway, I still don't see your work. Unless the image you show is actually the work you did? I thought it was the given solution.

as i think is said it the solution give nis the same as my work that how i did it then when i looked at solution it was the same but off by 1 factor of 1000..so i was confused so i asked thanks for the help