N S

17

SchoolDD.com

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www.schoolDD.com 1

17

17.1

)*+, 16 */0*1234456789: )1:;3*2*7< /0479=>2*7<0,89 :9? 923+ (Michael Faraday) 9;38>09J , K479=>2*7< L ,;L *445727 )1:;123445?89: 0+,;L9? 123445? 271:;12344579L1? !" 17.1.1 #$%$%&! !"

479=>2*7<63789:*727 :;123445:3789: )+*/0789:7/0*< v 289?M 9,3*2*7< B )1:0;7800;310+N789:7/0 99?)1*22*7<1:800;7800;31 7/0)7 P 7 Q (8*Q*/0) :;123445:?3789:;) Q P ;123445) Q P )3*/09, **89>44517 P 9, Q K80789:?,) 79?3003789: )1:R27)445 27/0445;??

I

B

I

I

B I

I v

I

B

B

Q

P

e B

v

I

www.schoolDD.com 2

17.1.2 ()$% *! + +%, !"--

+ . */07/022*7<7 479=>2*7<*72779L1 ;*? ∆B = B2 - B1;123445: I 7 + . */07/022*7<00)7 479=>2*7<*72779L177 ∆B = B2 - B1;123445: I 7 */0:789:,;L3*2*7<*727 )1:;123445 :79 ;0123445:789: ).), =3 / )01 2(3 # !"$!$#-- !"$%&!)4

B2 > B1

479=>2*7< 67 B1

N

I

N

∆ B = B2 - B1 B2

B1

BI I

∆ B

∆ B = B2 - B1

B2 B1

∆ B

BI I

479=>2*7< 67 B2

B2 < B1

N

I

N

www.schoolDD.com 3

1

)+ );0123445:789: 17.1.3 ()6*!( !" )+7+37*6/6 PQRS 0+3*2*7< */002N0 *7 0,2 xy 9+ 098< v 89,3*2*7< B )1:;27/0445:271123445: ?37 PQ 271 RS 8*79;123445: 3 PS 271 QR *;27/0445: 271123445: 11,0*0+299,;03*2*7<

.

M. ). .

v

B

v

B

N N S S

N N S S

y

x

S

R Q

P

I I B

B v

v

N S

. .

.

=. . K.

www.schoolDD.com 4

17.1.4 %%($ $

)79:0*080> , 16 */06123445 I1 70+3*2*7< B )1;21:7 F :7*9+ . )79;123445:7*899,3*2*7< ;0123445: I2 )1*;9+ . =)1*;8*9,;01234453 I1 )123445:;*080>? %% 27127/0445:? %% /0879, (Back emf) -+ &!$

1. L1*080>;** 098<0* v = 0 :*;123445979, I2 = 0 12344570*080>)1**39, I1- I2 = I1 /09,12344550 2. L1*080>:79* )1;123445979, I2 *;812344550 I1 :12344570*080>*77R I = I1- I2 K*080>*<3 (v ) I2 )1*3 99?12344567)1*03 (Imin) 3. */0*080>*7/0);*cd /0*38*)* 123445979, I2 )1*07 :12344567L19?** 271123445** */067R7 e )1:70)* 99?)):R808;3;=>)098*98; /089:0*080> R99?*080>**/027/04458 2

*080>/09,27/0445 12 78> L1*080>:)1;27/0445979, 10 78> 271*1234456*080> 8 20*2> 7*080>**8

+ . 23:0*080> 4451238 + . 23;123445:

I1

I1 B B F

F

N S I2 I2 B

B v

v

N S

www.schoolDD.com 5

1234456*080> I = I1 I2

= -

8 = -

8 =

R =

R = 0.25 Ω Ans 17.2

/0:;445 /0* R/0*/067;8 79445 7 797 R 79445 0979:2*7<445 /0:;445*310,*/0*080> * 2 ; /0 /0:;451238 271/0:;445123379, 17.2.1 $

% */002N0*7 7/0893*2*7< 479=>2*7<67 *727 )*27/0445: 271123445:;? =R123445)/0:;445 :*18> ;)L)+ L11,789?M9,3*2*7< ;0*<07 0+29,3*2*7< )**123445: 780* ;0*< ;*:**9,3*2*7< )*123445 ;*? 271**3 */0;0*<89?M 9,;03*2*7< =R8:21,7 0+299,3*2*7< */07*800 123445: <)1*77 271R+>09? /0)*0**;880> 2,,6= 2712 ): ;0123445 * ;941 I 271 t 123445 )/0:;44579L1? $ (Direct Current k D.C l)

0**;880> 2

I2 I2 B

B v

v

N S

I

I2

I1

12 V M

8:21,7

7 t /4 /2 3/4

0

123445 I

www.schoolDD.com 6

17.2.2 %

799,/0:;4451238 )128890**;880> *79L1R27/ 2 092)9 :12344500)/0:;445 0,2 2710,79*;8*994 123445)/0:;44579L1? % (Alternating Current k A.C. l) K80898 9,/0:;445123379, 4112344568989,7 271*89>179?3008989,7 )1*79L1*/099? */0 T /0, /077*, 1 0, 3*K f R379,0, *K):0,*07 1 ; 1 *K0445123379,* 50 0,80; (/0 50 Hz) 237* 50 0, 1 ; 271*89>R 220 78> ;)<2%

8:21,7

7 t /4 /2 3/4

0

123445 I

I2 I2 B

B v

v

N S

1 0,

7 t T/2 T 3T/2 2T

0

123445 I

1 0,

7 t T/2 T 3T/2 2T

0

*89> V

N S

www.schoolDD.com 7

R/0:;445123379, ;u*22*7<479=>2*7<89789: 123445:;?N789: 3*K634009 *80*27/ 2712*10, 17.2.3 3 R/0:;445123379, 445 10, 789: 79L1*/09 3 :** 120° =92719 87*22*7<K0+ 727479=>2*7< /0)*22*7< :;27/0445: 271123445:?79?3* 28)1*4389 120° 8***11,79?3* ):3+30*89>072871 ;?* 0*9 =3*K41*89> 9,707 28719+

3

2 1

N S

7 t 1

*89> V

7 t 2

7 t 3

www.schoolDD.com 8

!=%

/0:;445 3 43 )1*38000)79?3* 9?* 6 3 )1:3072871 80927807; )*9>445R+> */0,9,; (N) 337/0028710 3 3 )1R3*9>4452889,; ( L) 67;8 2713 79445)445 ;*32,,445123379, 3 43 4 3 (L 3 3 + N 1 3) 3:9,4458*,/09? R )803*4 33 0445 3 43 9,37 44543?9,/044580:79**9 97* 8+< 8*,/0 KR*080>445123379,8* *9445 3 43 =L?)18039? 3 3 0445 3 43 **89> *13*9,*080>45123379,8 0067;8 2713445 3 43 /03:79445 )1K+2,00R 3 3 :*8034* R1927173+3* 0)?*8e 44597143 */0;4459,4343 *445430/ 9*4458*8; /0:;445 R/0*/0 7 797 R 79445 79767;8445*)7 79*0 =)6*0?:*98 K; 2z3u*8; =K+8*?:7R0**93+ *99809,/0:;445 */0/0:<)1 7944500* 0)? 9 797*) 799> *K0?: 67;8123445)/08e =% *> -2 !

794453+3)3:79445 *93+3+ 79*0 34 271) 79*0;?34 */0*123767:

A

C

D

E F

B

3

2 1

N S

44543

220 V

37 (803 BDF 9)

220 V

220 V

*080> 3 43 27)4 3 43

www.schoolDD.com 9

)3* W = QV W = ItV (I = Q/t) W = I2Rt

271 P =

P = ItV

P = IV 3

4452 3*K3:79445 110 ;7988> ) 79*03+3N34 K3:7944563 100 *8 *8 0.20 0>* 10 ; *89> . 220 78> . 220,000 78> )>: P = 110x103 W , R = 0.20 Ω , t = 10 s . V= 220 V , W = ? ) W = I2Rt ---1 + R, t I ) P = IV

I = =

= 500 A

2 I 1 , W = (500)2x0.2x10 W = 500,000 J Ans . V = 220,000 , W = ? ) W = I2Rt ---1 + R, t I ) P = IV

I = =

, = 0.5 A

2 I 1 , W = (0.5)2x0.2x10 W = 0.5 J Ans - )89023 3:79445**117e *89>3+* /073+3 79*0 271K*89>3+*; 0);79) 1340445 3 43 /0)00,e34 )1K+3*445)34:7R89: 0)?7c8 0):*4459 7*8*34R71 99?*89>*13* 3:9,3:79445 /0 230,00078> 27)1*7*89> 73K4450 7/0 69,000 78> 2738**8e =)17*89>77/0 220 78> 3:9,8*,/0 0L> *027445

www.schoolDD.com 10

17.3 #- (Transformer)

*02745R0L>3:9, 7*89>445123379,3+?/08:7 0979:2*7<445 *310,9+ %)#-

*/080445123379, I1 =*27/0445 E1 7 *N+*; )1:; 727479=>2*7< (/0)123379, I150) 479=>2*7<727?)1627<00K78;N+*; 271)1::; 27/0445: E2 271123445 : I2 78;N+*; 3*K*39* 9u>027/0445 9,):0,079? *027445* 2 ; /0 1. *027? ( N2 > N1 : E2 > E1 ) 2. *0277 ( N2 < N1 : E2 < E1 ) *027:K0 79445)7*N+*;*978;N+*; 271)17M 1*89>9? K**3+3 791K0 7944507*N+*; W1 = 79445078;N+*; W2

=

/0

=

*/0 V1 271 V2 R*89> 17 07*N+*; 27178;N+*; 8*7:9,

310,0*027

78;N+*; ):0, N2 0,

7*N+*; ):0, N1 0,

27<00267/0,M

R

I2

E2 I2

E1

I1

I1

00

N1 N2

N1 N2

N1 N2

www.schoolDD.com 11

*/0 P1 = :79445 P2 = :7944500 (Eddy current)

123 R123445:;?27< /0*)727479=>2*7< 6)7*N+*; 978;N+*; R67:;*027<9? :*3+3 79445 )::79445)78;N+*;0:794457*N+*; ( P2 < P1 ) /073+3 79445R*027<09/0*)123 )80002,,27<*12303 267<00 7 e 26 =09*M, e9?126227<9?2 6-%)#-

1. *027445 9,4123379, 2. K809,41238 8039,3;8=>- R)91 /0 1237*3*:3*0

3.

= =

4. *027? N2 > N1 , E2 > E1 *0277 N2 < N1 , E2 < E1 5. P1 = P2 4

*027/0*7*N+*; ): 200 0, 27178;N+*; ): 50 0, 9,27/0445 12 78> *1234456 7*N+*; 0.5 20*2> K**3+3 797 12344578;N+*; )1*

)

=

E2 = E1 !N1N2%

= 12! 50200%

P1 = P2

N1 = 200 N2 = 50

I2 = ? I1 = 0.5

E1 = 12

99? /0 I1V1 = I2V2

www.schoolDD.com 12

E2 = 3 V = V2 ) P1 = P2 I1V1 = I2V2 V1 = E1 , V2 = E2 2)1 0.5x12 = I2x2 I2 = 2 A Ans 5

*027/0*7*N+*; ): 20 0, 27178;N+*; ): 100 0, =800+9,898 25 0>* K 7944527*N+*; 20 )+780+70*,> )1*123445 6898 25 0>* 7944527*N+*; 25 )+780+70*,> )1<* R)+780+70*,> =R0 79801) (W/ Q) 9</078>90 ) W = QV

V = (

271 E1 = V1 = 20 V

)

=

E2 = E1 !N1N2%

= 20!10020 % E2 = 100 V ) V = IR

I2 =

= )

I2 = 4 A Ans

N1 = 20 N2 = 100

R = 25 Ω E1 = 20

www.schoolDD.com 13

17.4 % $!3%

*/0:898 R 809,/0:;445123379, AC (3979L> ) )1*123379, (i) 6898 271**89> (v) 179?300898 0;*L9?307278*7 94 =*79L1R4>9=> 271R8*3* i 271 v R123445 271*89>7 t e Im 271 Vm R1234453+3 271*89>3+3 P); % %

3*KQ00>* 9,445 123379,9,4451238

%) %

:099,4451238 3*K:79445 (p) 0445123379,)3*

Im 7 t

T/2 T 3T/2 2T 0

123445 i

- Im - Vm

Vm 7 t

T/2 T 3T/2 2T 0

*89> v

i = Im sin *t

v = Vm sin *t

ω = 098<;**0*7

= , =

-. = 2f

v = i R

Vm = Im R

AC

R i

V

www.schoolDD.com 14

;)L41123379, i , *89> v , :79445 p 9,7 t 0445123379, )1< M70123445 271*89> 1 , *R+> 271M70:79445*R, ;)L4

p = i v

Pm = Im Vm

i v

- Vm

Pm Vm Im 7 t

T/2 T 0

i , v , p

- Im

p

iM7 vM7 -

+ t T

0

i , v

iM7 = //040 /84

= 0 (;/0* + , - )

vM7 = 1/040 184

= 0

T

p = i v pM7

t

p

Pm

0

pM7 = 2

= ½ ImVm

= ½ Im(Im R) = ½ (2)Vm

pM7 = Im

2 R = 2

Im t 0

i

- Im

T

i2M7 = Im2 /2 t

i2

Im2

0

- Vm

Vm t 0

v

T

v2M7 = Vm2 /2 t

v2

Vm2

0

p , Pm R,3*0 1 i 9, v *4389

www.schoolDD.com 15

)4)1 (i2)M7 = ½ Im

2 271 (v2)M7 = ½ Vm2

K Irms = 3!i%M7 = 52√ R30 0:7930M70123445

Vrms = 3!v%M7 = 2√ R30 0:7930M70*89>

3*KM70:79445)3*

pM7 = 2 = ½ ImVm =

52√ x 2√ = Irms Vrms

Irms 271 Vrms ?!%& /0!$ =R0)*;80>9123445 /0*89> 0445123379,8*,/09 271,,9, I 271V 04451238 6- , $!3% % ) % 1. 123379, i = Im sin 7t (Im = 123379,3+3) *89> v = Vm sin 7t (Vm = *89>3+3) 2. Q00>*9,1238 (V = IR) v = iR Vm = ImR 3. :794459,:794451238 (P = IV) p = iv Pm = Im Vm

pM7 = 2 = 522

= IrmsVrms

4. 300:7930M7

Irms = 52√

Vrms = 2√

6

)445123379,*123445 i 2717 t 8*3* i = 2 sin (314t) ) . 1234453+3 . *K . Irms )3*123379, i = Im sin 7t ))> i = 2 sin (314t )

www.schoolDD.com 16

,, 2 3*)1 1234453+3 Im = 2 A Ans 098<;** 7 = 314 2πf = 314

f = 9 :9.

= 50 Hz Ans

Irms = 52√ =

√ = √2 A Ans

7

704 40 988> , 220 78> 809,27:;445123379, 220 78> ) . *80704 . 1234453+36704 . :794453+3 . :79445M7

. *80704 R ;)L704 pM7 = 40 W , Vrms = 220 V

) P = IV = !%V

=

R = <2=

>M7 =

R = 1210 Ω Ans

. 1234453+36704 Im ) Irms =

52√

Im = √2 Irms = √2 Irms = √2 !<2=

%

= √2 !

% Im = 0.26 A Ans

AC Vrms = 220

40 W , 220 V

i

www.schoolDD.com 17

. :794453+3 Pm ) Pm = ImVm = Im(√2 Vrms) = 0.26(√2 x220) Pm = 80 W Ans

. :79445M7 pM7

) pM7 = 2

= ?

pM7 = 40 W Ans 8

445123379,8*,/0 */0978>*;80> 0 220 78> 271*/020**;80>91230 10 *;77;20*2> ) *89>3+3 2711234453+3

))> Vrms = 220 V 271 Irms = 10 mA

Vm ) Vrms = 2√

Vm = √2 Vrms = √2 x220 Vm = 311 V Ans

Im ) Irms = 52√

Im = √2 Irms = √2 x10 Im = 14 mA Ans 17.5 2$%"-26 $%

)89<,1) + . 23))89<,1)27141 i , v 9, t */08089<,1) C 9,/0:;445123379, ,123445 689<,1) iC )1*43:*89>089<,1) vC 0+ 90° /0

@ 9+

AC

C i

V

iC

vC t 0

i , v

iC *43: vC 0+ 90°

www.schoolDD.com 18

2$%

*/08089: L 9,/0:;445123379, ,*89>089: vL *43:123689: iL 0+ 90° /0

@ 9+ .

6- %&! R , L , C

AC

L i

V iL

vL t 0

i , v

i *43: v 0+ @

i 271 v *4389

v

R

i

C

v i

v = Vm sin 7t i = Im sin 7t p = iv Pm = ImVm pM7 = Pm/2

v = Vm sin 7t i = Im sin (7t + π/2) p = iv Pm = ImVm/2 pM7 = 0

v = Vm sin 7t

i = Im sin (7t - π/2) p = iv Pm = ImVm/2 pM7 = 0

Pm Vm p = i v

t t

i , v p

Im

Im , Vm p = i v

i v

t

i , v t

p Pm

Pm Im , Vm

i

v t

i , v p = i v

t

p L

v i

v *43: i 0+ @

www.schoolDD.com 19

$#)$%"-26 $%

*8089<,1) ( XC ) /0*8);8N 0*) 271*8089: ( XL ) /0*8);8N 0*: *R0>* )00>*9

00>* R = 5

XC = <2=

5<2=

271 XL = <2=

5<2=

0)?93*K XC 271 XL 0;u +*K027:;445123379, f *) C 271*: L )3*

XC = AB =

-C B

XL = 7L = 2f L f = *K027:;445 (;>=) C = *)089<,1) (49) L = *:089: () 9

)445123379,10, 898 89<,1) 27189:9+ K20**;80>9123445 10 *;77;20*2> 27178>*;80>9*89>170898 89<,1) 27189: 8.0 , 12.0 2716.0 78>8*7:9, )*8 *8);8N 0*) 271*8);8N 0*: 0) /0) R , C , L 8092,,0* 99?)1*12369/0 10 mA =920**;80> Irms = 10 mA ;)L898 Vrms = 8 V

L

i

C R

www.schoolDD.com 20

R ) R = <2=

5<2= = ?

:D

R = 800 Ω Ans ;)L89<,1) Vrms = 12 V

XC ) XC = <2=

5<2= =

:D

XC = 1200 Ω Ans ;)L89: Vrms = 6 V

XL ) XL = <2=

5<2= = E

:D

XL = 600 Ω Ans 10

/0:;445123379,**K 50 ;>= rms 027/0445 12 78> ) rms 0123445) */080/0:;445?9, . 898**8 10 0>* . 89<,1)**) 33 *49 . 89:**: 20 *;77; .

) V = I R /0 I =

Irms = <2=

=

Irms = 1.2 A Ans .

f = 50 Hz Vrms = 12 V

R

f = 50 Hz Vrms = 12 V

C = 33 FF

www.schoolDD.com 21

XC ) XC = AB =

-C B =

:9. :):99:DG

XC = 96.5 Ω

Irms = <2=

HI =

JE.)

Irms = 0.12 A Ans . XL ) XL = 7L = 2f L = 2x3.14x50x20x10

-3

XL = 6.28 Ω

Irms = <2=

HK =

E.?

Irms = 1.91 A Ans 17.6 +=%)(^#(# /04459)1*8971,*89> 123 271:794459,/0445 *89> 271123 R rms 3:79445)1R:79445M7 ( pM7 ) /04459, 2713*K:L)3* pM7 = IrmsVrmscos θ */0 θ /0 *288430123445 271*89>445 271 cos θ /08910,:790/0445 8;*9, 1 (θ = 0°)

f = 50 Hz Vrms = 12 V

L = 20 mH

PHILIPS 97*89?8z1 HR 3312 BLADE SIZE 300 mm (12l) 29445 VOLTAGE 220 V 50 Hz :79445 POWER 45 W 123445 AMPERE 0.25 A 13;u;N 0.83 m3/min/W

www.schoolDD.com 22

- K i 271 v *4389 θ = 0° --> cos θ = 1 K i 271 v *4389 θ M 0° --> cos θ < 1 99?3*K:L 79445 W )+77 t ; )3*

pM7 =

W = pM7 t !

*/048034 =;) 79445 (W) 794453:9,:L4R ;7988>9* *99 (UNIT ) 1 = 1 ;7988>9* 99?*/080 79445 /0;4 8027) 988>; (/0)+7) R ;7988>9* ))1,4 - pM7 0)/0445 )19, pM7 8989? 1 pM7 089<,1) 27189:*R+> 11

*/080*0445 485 988> 9,27:;445 220 78> ) . 1234456*0 . *80*0 . 79445R7 0.5 9* . )0 . 803445)4 K0984R 3 ,80 ))> pM7 = 485 W , Vrms = 220 V , t = 0.5x60x60 = 1800 s 271 8910,:79 cos θ = 1.0 . Irms = ? ) pM7 = IrmsVrmscos θ

Irms = >M7<2=

= ?)

(cos θ = 1.0)

Irms = 2.2 A Ans . R = ?

) R = <2=

5<2= =

.

R = 100 Ω Ans

v = 220 W

i

www.schoolDD.com 23

. W = ?

) pM7 =

W = pM7 t = 485x1800 W = 8.73x105 J Ans . 445 )0 . W = 8.73x105 J (= 988>;) 27R ;7988>9* ( = 1 )

W = ?.N9:O

:E:E

W = 0.24 ;7988>9* = 0.24 8034 3x0.24 = 0.72 , Ans 12

)445123379, *123445 i R i = 5 sin (7t - 40°) 271**89>R v = 15 sin (7t + 20°) ) . 8910,:79 . :79445M7)2) ))> i = 5 sin (7t - 40°) 271 v = 15 sin (7t + 20°) )13 v *43: i 0+ 20-(-40) = 60° 271 Im = 5 A , Vm = 15 () i = Im sin 7t 271 v = Vm sin 7t) . 8910,:79 cos θ = ? , θ = 60° cos θ = cos 60° cos θ = ½ = 0.5 Ans . pM7 = ? ) pM7 = IrmsVrms cos θ

= 52√ x 2√ x cos 60 = )

√ x )√ x = N)

pM7 = 18.75 W Ans 13

)123445 I1 , I2 271 I3 )4450,799+ */0/04459?*:79: y x

I1 I2

I3

704 40 W

/0* 800 W 120 V

704 40 W

www.schoolDD.com 24

)+ /04459?*8092,, **89>17/04452871099/0 Vrms = 120 V 1236/0445287109) pM7 = IrmsVrms Irms =

>M7<2=

y =

= 9 A

x = ?

= 9 A

I1 =

= 9 A Ans

I2 = x + I1 = 9 + 9 = 7 A Ans

I3 = y + x + I1 = 9 +

9 + 9 = 7.33 A Ans

17.7 2(#

L

L

L

L

N N

N N 704

31 40 43>*

26,*445

L N

31 4*

89,

L L L L

N N

33445 3 43 4 3

890 )445,

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/0445, *802,, /03 /090)1**671,9,/00/ e */080804,<:803430445 3 43 =3*9> (3 L) 9,37 (3 N) =*9>445R+> 3 L 271 N )1K+809,26,*445 =R,*) 794459?*, )9?)*34938 e 0, !-%)&6

1. = %$# (cut-out) R0L>89/080)445349?303 8;)1*897,01234453+3 271*89>3+3 K1236*: 31 4)10)* /0K31 49,*89>3+: )1:123445919?031 4 /0509123445,3+*; )*8;43>31 4 27126,* - *31 4026,* < /002 271,* 3 794459)4450 8*38 e 0, )9?7 )9?, /)9 /02,*8*;/0445 9??< /044528713R0;31809 380=0*33 *8089)445,9?* 2. b R0L>89)445*/0*1234456)*; 43>:71*)70*78: 7163*,9,819 */0*123445643>*;8; 43>)1027170*717))9 :;89)445098*98; 043> :R01234453+33*K643>43>* 14

,79445=**89> 220 78> K/0445980? *0 600 988> 8 750 988> 8+< 100 988> 9> 150 988> 704 40 988> 3 271704 20 988> 5 43>* 043> *K123445*0/04459?* /0)/04458092,, Vrms 9 9, 220 V Irms 6/0445287189 ) pM7 = Irms Vrms Irms =

>M7<2=

*0 Irms1 = E

8 Irms2 = N)

8+< Irms3 =

9> Irms4 = )

704 Irms5 = :9

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704 Irms6 = :)

043> Irms1 + Irms2 + Irms3 + Irms4 + Irms5 + Irms6 = E 0N)00)00

= 8.27 A

/0 ) pM7* = 600 + 750 + 100 + 150 + (40x3) + (20x5) = 1820 W 271 Vrms = 220 V

Irms = ?

= 8.27 A 43>*1*L 9 A /0)43>*9R 10 A )8043> 10 A Ans - L/0445*8910,:790 1 Irms )1**:L )8043>;:L 271;* 0)1*:43>78*8; 15

704 100 988> 5 271/0:*< 200 988> 5 /0 8090 27809,27:;445 27/0445 200 78> 43> 0L>9?*8092,, 99? Vrms 9 9, 200 V Irms 60L>287189 ) pM7 = Irms Vrms Irms =

>M7<2=

704 Irms =

= 0.5 A

/0:*< Irms =

= 1.0 A 043> = 0.5x5 + 1.0x5 = 7.5 A 43> 8 A Ans

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