Can someone check my Physics working?

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The user seeks verification of their physics calculations regarding an inductor and a capacitor. For the inductor, they calculated an inductance of 0.14H and a maximum current of 3.2A based on a 100 Vrms voltage at 50 Hz. For the capacitor, they found a maximum current of 0.13A when connected to a 110 Vrms outlet at 60 Hz. The response confirms the calculations are correct but advises maintaining more significant figures in intermediate steps to reduce rounding errors. Overall, the user's physics work is accurate, but attention to detail in calculations and unit labeling is recommended.
cseet
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Hi all,
can somebody pls check whether or not I'm in the right direction with my workings and answers. If not, can you pls advise why I've gone wrong?

thanks

question 1:
1. An inductor has a 54 ohm reactance at 60 Hz. What is the maximum current if this inductor is connected to a 50 Hz source that produces a 100 Vrms voltage?

answer:
L=?
XL = (2 pie f)(L)
54 = (2 pie 60) L
L = 54 / (2 pie 60) = 0.14H

Imax = ?
f = 50 Hz
Vrms = 100V
V max = 100 * sq root of 2

XL = wL
= (2 pie 50) (0.14)
= 43.98 = 44 ohm

therefore
Imax = Vmax / XL
= (100 * sq root 2) / 44 = 3.2A

question 2:

What maximum current is delivered by a 2.2 microF capacitor when connected to a North American outlet where Vrms = 110 V and f = 60 Hz

answer
Imax = ?
Xc = 1 / (wC) = 1 / [(2 pie 60) * (2.2E-6)]
= 1206 ohm
Imax = Vmax / Xc
= (110 * sq root of 2) / 1206
= 0.13A

thanks again
cseet
 
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Looks good to me.

The only thing I could suggest is that when you wish to give your answer to 2 significant figures (which is great!) to be sure to carry all intermediate calculations to at least 3 figures to minimize any round off error. For example, in problem #1 you round off the inductance to 0.14 when a more accurate answer is 0.143. Wait until the last step to round off your answer to a sensible number of figures.
 


Your working and answers for both questions seem to be correct. I would suggest double checking your calculations and units to ensure accuracy. Also, make sure to label your final answers with the correct units (ohms and amperes). Overall, good job with your Physics work! Keep up the good work and always remember to double check your work to ensure accuracy.
 
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