Page 27 - كتاب تاسع فيزياء الفصل 2 تفاعلي. هويدا محمود

zi a z5 0-a c>Va ¿ O5 a W>a ¿ ² x3yVa

ÎS P ± ÍRú ٠Э ÓR Э Õ ›—›› ÎÒP ± d ];8: E9
­
c ¯ ¹b b ± ` C<=9 ^0 d ± E C2 ± ` 40% ÎbÛ
³»P79 C< 6 d Ðb8
E ; ± ÑQ Ò .³P=6 E C ©E C2 ± »P< C Õ b= R M± E C2 ± ^8 C ˜­ £—››
³«C6 ÐA d C C Ò –³P=6 ³»P c ¯ R=Û 5 d ± E9 ±P ± .C Õ C= ­ E C2 ± a= »P<Ù R ¬ Õ 8 R º± ˜²

.40% [9 ÎS P ± ÍRú .²C
­ E R º± ©E C2 ± »P ÏP C;:L < ±ºC: ›š—››

›—›› ÎC ³«C68 ± ²C

P S .E C; d P40 Z R dgC R< ÍRú ÏPØ Ù E »C ± ³P=6: ± E C2 ± _ 7 –`=K 4 ¼C< ³«C6 ²C
( 5000ௗ-) »±P7: ²C Û R ±Ò P40:9 E= ºC ± ZhÒ E C .E9 ±P ± E C2 ± c9

[9 _8 –(8000ௗ:) ÍRú : ± ³»P F C ±ºA .(8ௗs) d C C Õ C ³«C68 ± Э ›—›› ÎÒP ± ` ÓR Э ];8: Ò
©a «C6 c9 E C2 ± R=L 5 ³«C6 ²C C;;8: Ò .E b E ; c24

¤E »C ± ³P=6: ± ³»P7 ± ¤d Š± b ; ±

p= E 100% × E »C ± ³P=6: ± E C2 ± § ³«C68 ±
t E9 ±P ± E C2 ±

= 45 000 J d NhK b: ± `= 5; ± ^= Òº ·C 0: ± ¹ÒK SÙ C P;4
8s 15ௗJ H ; Ò –100ௗJ C »±P7 E=gC R< E C2 ¢—›› ³»b0 ±

= 5625 W b ; ± c9 a «C6 D Ø Ù –³P=6: ± E=gb1 ± E C2 ± `
¤d Š±
100% × E »C ± ³P=6: ± ³»P7 ± § ³«C68 ±
E9 ±P ± ³»P7 ± ¤`= 5; ± ^= Ôº ·C 0: ± ³«C6

= 5625 W × 100% 15 × 100% = 15%
8000 W 100

= 70% E9
­

E9
­ ´C C= ± ` E C29 R ú b: ± ·C 0: ± ³«C6 D ± ››—››
.ž—›› ^8/ ± d ³R C3 ±
E C2 ± »±P7 C .(10%) ·C 0 ³«C6 [9 ›—››
H ;= E= C ^ d C< ÑP ÒS D d ± E=gC R<8 ± _Ê 6 C ^Ê:4 EÊ=gCÊ R< EÊ CÊ EÊ2K Ê HÊ Ú ;Ù ›œ—››
C P; E=gC R<8 ± E C2 ± ` (100ௗMJ) ÔR ±
©E= C ± d E=gb1 ± E C2 ± ` (20ௗJ) .C< «C6 D ± .(400ௗMJ) C »±P7 E C2 ¹ÒK SÙ
E=gC ÒR< E C E2K ` E »C ± ³»P7 ± [9 ›ž—››
E= ºC ± ZhÒ E C d R=L 5 ± [9 Ò .(2.2ௗMW) ÎÒK M± d
±»P ± ^06 ± ` E; C ± ³P b ± d C7Õ C
C;6jÒ
(2.5ௗMJ) ´C;= »b ± R E= C ± d X C ± «C:9 C;;8: ] Q .E C2 ± a= ^7 ; ÔQ ± ÎPK 4: ± d ³»P7Ù ± Э

.E C2 ± E2K ³«C6 D ± .E= C ± d

.C1Õ ­ E »C ± ³P=6: ± ³»P7 C ¼C< ± ³«C6 ` R Û 4 Э

100% × E »C ± ³P=6: ± ³»P7 ± § ³«C68 ±
E9 ±P ± ³»P7 ±

œ œ