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#28 Why the Circuit Power factor (Cos θ) Decreases, when Inductance (L) or inductive reactance (XL) increases, In inductive circuit? Why the Circuit Power factor (Cos θ) Decreases, when Inductance (L) or inductive reactance (XL) increases, In inductive circuit?

Why the Circuit Power factor (Cos θ) Decreases, when Inductance (L) or inductive reactance (XL) increases, In inductive circuit? OR Explain the statement that  “  the Circuit Power factor   (Cos θ)  Decreases,  when Inductance (L) or inductive reactance (X L ) increases” Explanation:    Suppose,  when Inductance (L) = 0.02H V=220, R= 10 Ω,  L=0.02 H , f=50Hz. X L  = 2πfL = 2 x 3.1415 x 50 x 0.02 = 6.28 Ω Z = √ (R 2 +X L 2 ) = √ (10 2  + 6.28 2 ) = 11.8 Ω Cos θ = R/Z = 10/11.05 =   0.85 Now we increases Inductance (L) form 0.02 H to 0.04 H, V=220, R= 10 Ω,  L=0.04 H , f=50Hz. X L  = 2πfL= 2 x 3.1415 x 50 x 0.04 = 12.56 Ω Z = √ (R 2 +X L 2 ) = √ (10 2  + 12.56 2 ) = 16.05 Ω Cos θ = R/Z = 10/16.05 =  0.75 Conclusion : We can see that, When inductance (L) was 0.02, then circuit current were 18.64 A, and Circuit power factor was (Co...
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#22 Why we can’t store AC in Batteries instead of DC.or Can we store AC in batteries instead of DC?

Why we can’t store AC in Batteries instead of DC.or Can we store AC in batteries instead of DC? We  cannot store AC in batteries  because AC changes their polarity up to 50 (When frequency = 50 Hz) or 60 (When frequency = 60 Hz) times in a second. Therefore the battery terminals keep changing Positive (+ve) becomes Negative (-Ve) and vice versa, but the battery cannot change their terminals with the same speed so that’s why we can’t store AC in Batteries. in addition, when we  connect a battery with AC Supply , then It will charge during positive half cycle and discharge during negative half cycle, because the Positive (+ve) half cycle cancel the negative (-Ve) half cycle, so the  average voltage or current in a complete cycle is Zero . So there is no chance to store AC in the Batteries. If you want more books, slide, ppt's and notes,Request in the comment section. Visit the site for more knowledge and share this site link to the needy one....
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#5 QUANTITATIVE APTITUDE BY R.S.AGGRAWAL

A BOOK OF QUANTITATIVE APTITUDE BY R.S.AGGRAWAL CONTAINING ALL  SOLVED AND UNSOLVED EXAMPLE CLICK HERE  TO DOWNLOAD THE BOOK . . . . . . ↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓ . . . . . https://drive.google.com/open?id=0B9buDBvxkr5fZWVhRDBOTzFpbzA . . . . . . . If you want more book online you can request in the comment section , Visit here for more books and share this site link with the needy one.  Thank You
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