Please help and show work, keep getting wrong.?

2020-07-20 12:17 pm
Physics 2

回答 (2)

2020-07-20 2:55 pm
Please show you work and thus we will know how you keep getting wrong and how to help you.
2020-07-20 3:09 pm
Not all , just the major part of ....

1)
Pls see the enclosed sketch 
A = 0.035m^2 = 350 cm^2 = 350/2.54^2 = 54.25 square inches = PI*R^2
R = √ 54.25/3.1416 = 4.16''
H = 22/2.54 = 8.66''
L = 45*10^3 μ H 
N = √ 45*10^3*(9*4.16+10*8.66)/4.16^2 = 568 turns

2)
turns ratio k = 18
V2 = V1/k = 120/18 = 10*2/3 = 20/3 of volt (≅ 6.67)

4)
timeconstant T = L/r = 3000/8 = 375*10^-6 sec 
I2 = V/R*(1-e^-(200/375) = 0,5*(1-2.7182818^-(200/375) = 0.207 A 
I1 =  V/R*(1-e^-(100/375) = 0,5*(1-2.7182818^-(100/375) = 0.117 A
aver. induced emf = E = V-(r*(I1+I2)/2) =  40-80*(0.207+0.117)/2 = 27.0 V 
aver. voltage across res. Δ V = V-E = 40-27 = 13.0 V 

5)
ω = 120PI = 377 rad/sec 
Xc = 10^6/(377*120) = 22.10 ohm
Xℓ = 377*50*10^-3 = 18.85 ohm < Xc (current will be leading) 
impedance Z = √ R^2+(Xc-Xℓ )^2 = √ 18^2+(22.10-18.85)^2 = 18.3 ohm 
Ipeak = V/ Z = 120/ 18.3  = 6.56 A 
Irms = Ipeak /√2 = 6,56/1.41 = 4.65 A 
leading angle = arctan (Xc-Xℓ ) / R = arctan 3.25/18 = 10.2°
peak voltage across capacitor = Xc*Ipeak = 22.1*6.56 = 145 V 
rms voltage across capacitor = Xc*Irms = 22.1*4.65 = 103 V 







 


收錄日期: 2021-04-18 18:35:41
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20200720041731AAuTPQ4

檢視 Wayback Machine 備份