Page 66 - كتاب تاسع فيزياء الفصل 2 تفاعلي. هويدا محمود

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1o^a NU -a r† Za q -o"a X1Uq 0 y† a £ 1:M 6e *a -%ra

³»P7 ± ½C= ³P Ò û R4 C1Õ ­ E ¹C4: ± ÑQ C R ú QÙ E=gC R<8 ± ³»P7 ±
:(W) ´±b ±
R<Ú 3Ù d6 R4 \0Ø 9 Ù E=gC R<8 ± ³S< M± _34 c9 F K
E= C ± d P ±Ò Îb b P ±b ± ´±b ± ³»P7 ± -›Ÿ ³»b0 ± d ÎC : ± `=Û Ù .E=9=5/ ± C< »P
´±b ± ³P b C<= ¯ »C/Ù d ±Ò –û ÒÒR8 C ÐR6 E=9=5/ ±
1 W = 1 J/s –C ¼C< E=9=5/ ± ³»P7 ± `=Û Ù .(kW) ´±Òb9=8 ± Ò­ (W)
C; R=/Ù Ò –C R=Û 5 Ò­ E C2 ± ¼C< ± a ^7; ÔQ ± ÎPK 4: ±
E=:9 ´C 920 ¼C< ± C< d ± Power (P) ³»P79 c0 M± PÛ ± c ¯
¼C< ± ^5 / C P; d =gR ± dgC R<8 ± »C=Û ± »P0 `
Ò­ R ¬ c ¯ ÐC8 ` E C2 ± ^7 ÎPK 4 Ù :Power (P) ³»P7 ±
.C< <
± Ò­ C µP P; C<9 b .a »P ^ C8

d ÒP ± ÏC3; ± d ³»P7 ± ½C= ³P Ò :Watt (W) ´±b ±
.(SI) ´±P b9

dgC R< P< Ù »P0 Ò­ E=9 ± a ^7; ÔQ ± ÎPK 4: ± P: 4 ŽcK `w|^™TÐ ‡ZcdTÐ Ð{v p—« >ô ¾-¼À ÒڍZTÐ
E=gC R<8 ± E4 ±P ± ³bK 7 ± c9 C ³Rg±¹ c ¯ E C2 ± R ¬ †wíí|bwmX ë|Q ‹X `cTÐ Ê}›TÐ
Î ` Z PÙ ÔQ ± »C=Û ±Ò –»P0:9 (dgC R<8 ± P< Ù ±’
D Ø Ù û= E= Š± ´„¹C4: ± `=Û .E=gC R<8 ± ³Rg±P ±

:E=gC R<8 ± ³»P7 ±

P< Ù ± ÌR × dgC R<8 ± »C= ± ³PÛ = ³»P7 ±

P=IV

:E ¹C4: E2 R ´±P b E ¹C4: ± ÑQ R L Q ^1Û 6Ù P

F bo × R= ­ = ´±b ±

1ௗW = 1ௗA × 1ௗV

C<9 b Ò­ R ¬ c ¯ ÐC8 ` E C2 ± ^7 ÎPK 4 d ³»P7 ±

R Û Q E bÛ : ± E C2 ± :C µP P;
´±P b ± ϱP
C E ¹C4: ± R Û Q Э ] ^<
M± ` ÌRØ 5 :Ù ± ` S ±
= E=gC R<8 ± ³»P7 ±
.´C=:Û 8 ± ϱP
± ` R ­

E C2 ± ²C P= E
t
–` S ± × ³»P7 ± = E bÛ : ± E C2 ± Э C:
û R4 R Û Q Э D .E bÛ : ± E C2 ± E S R ± ^ ú :
E ¹C4 «C2 ˆ P = I࣯9 E ¹C4: C ³»P7 ± ` W b4 ± C;;8:
:E E bÛ : ± E C2 ± .ÎÒK M± d
±»P ± ^06 ± d E; C ± ³P b ± ` ±Q ³»P7 ±

X7 T= Ò –E bÛ : ± E C2 ± ñb ­ Z=: c9 \ 2; b<

.«C R<8 ±

` S ± × P< Ù ± ÌR × dgC R<8 ± »C=Û ± ³PÛ = E bÛ : ± E C2 ±

E=IVt

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