LEY DE OHM (7)

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

CONTENIDO  

Pág.

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Resumen

2

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INDICE GRÁFICAS Y TABLAS TABLAS   ,. TABLA , 2. TABLA 2

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UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

I.

LEY DE OHM

Resumen

En '( )*(+"#+( se $e*##+% e1)e*#men"('men"e '( 'e3 &e O:m 3 '( #n'uen+#( &e '(s *es#s"en+#(s #n"e*n(s &e '%s #ns"*umen"%s &e me&#&(; en e' +á'+u'% &e '%s $('%*es &e '(s *es#s"en+#(s. P*#me*(men"e se *e('#ue n%s #n&#+( >ue e' $%'"(!e ()'#+(&% es &#*e+"(men"e )*%)%*+#%n(' ( '( #n"ens#&(& &e +%**#en"e; =s"( (se$e*(+#/n es $á'#&( s# su)%nem%s >ue '( "em)e*("u*( &e' +%n&u+"%* se m(n"#ene +%ns"(n"e. V α  R '1( V RI 

A '( +%ns"(n"e &e )*%)%*+#%n('#&(& se '( &en%m#n( Res#s"en+#( e'=+"*#+( >ue "#ene +%m% un#&(& &e me&#&( e' %:m#% ?ς@. '2(  R =

V   I 

Es"e #m)%*"(n"e *esu'"(&% es $á'#&% )(*( +%n&u+"%*es me"á'#+%s 3 se +%n%+e +%m% '( 'e3 &e O:m. T%&% +%n&u+"%* ?e1+e)"% un su)e*+%n&u+"%*@ "#ene un( *es#s"en+#( >ue es '( %)%s#+#/n >ue =s"e )*esen"( ( '( +#*+u'(+#/n &e +%**#en"e e'=+"*#+(. E1#s"en *es#s"en+#(s >ue se +%ns"*u3en +%n un $('%* #!% 3 >ue %+u)(n )%+% $%'umen; e' $('%* &e es"(s *es#s"en+#(s es mu3 g*(n&e +%m)(*(&% +%n e' &e '%s +('es >ue se u"#'#ue )ue&en &#s#)(* % '( #n"ens#&(& % '( "ens#/n má1#m( >ue )ue&en s%)%*"(*. Es"(s m(gn#"u&es es"án *e'(+#%n(&(s )%*  P 

m

=  I 

2

 R = V  I 

m

m

m

Pm = Potencia m!ima disipada Im  Intensidad de corriente m!ima Vm = Volta"e o Tensión m!ima 979

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

P(*( *e('#ue #n&#+( e' (m)e*-me"*% es"á &(&( )%* '/(  I a

959

=  I r  +

I v

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

A&emás

'0(  I v

=

V   Rv

En"%n+es

'(  I v

=  I a −

V   Rv

V  &.&.). >ue m(*+( e' $%'"-me"*% en"*e '%s )un"%s A 3 B P%* '% "(n"%; e' $('%* &e '( *es#s"en+#( se*á

 R =

'(

V   I r 

V 

=

 I a

−

V   Rv

S# se ()'#+(*( &#*e+"(men"e '( 'e3 &e O:m

I '3(  R

=

V   I a

E' e**%* en '( me&#+#/n &e I*   es n% :(e* +%ns#&e*(&% '( #n"ens#&(& &e +%**#en"e >ue +#*+u'( )%* e' $%'"-me"*%; es &e+#* '14(

∆ I r  =  I a −  I r  =

I v

E' e**%* *e'("#$%

'11(

∆ I r 

 I r 

=

 I v  I r 

C%m% e' $%'"-me"*% se '% +%ne+"( en )(*('e'% ( '( *es#s"en+#( '12( V  =  I r  R =  I v Rv '1)(

9J9

 I v  I r 

=

 R  Rv

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

Segn '( e+. ?,4@ )%&*-( ()'#+(*se &#*e+"(men"e '( 'e3 &e O:m; s#n ee+"u(* n#ngun( +%**e++#/n )(*( I( se e' +%+#en"e R K R $ es mu+:% men%* (' e**%* &e' '-m#"e &e '%s #ns"*umen"%s u"#'#ue se &#s#)( en e' $%'"-me"*%; "(m#=n &ee +um)'#*se '( +%n&#+#/n '15(. b( mperímetro entre las coneiones del voltímetro

&igura 5 mperímetro entre las coneiones del voltímetro

En es"e +(s% e' (m)e*-me"*% &e"e+"( e' $('%* I(  I* ; )%* es"(* +%ne+"(&% en se*#e ( '( *es#s"en+#(. E' $%'"-me"*% m#&e '( &.&.). en"*e '%s )un"%s A 3 B V  =  I r  R +  I r  Ra

 R =

V  −  I r  Ra

'10(  R =

 I r  V   I r 

−

Ra

E' e**%* en '( me&#+#/n es n% :(e* +%ns#&e*(&% '( *es#s"en+#( #n"e*n( &e' (m)e*-me"*% I '1( ∆ R =  R −  R =  Ra

989

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

E' e**%* *e'("#$%

'1(

∆ R

 R

=

 Ra  R

Se )%&*-( ()'#+(* &#*e+"(men"e '( 'e3 &e O:m; s#em)*e >ue '( *e'(+#/n R (  K R se( mu+:% men%* >ue e' e**%* (' e**%* '-m#"e &e '%( #ns"*umen"%s &e me&#&(. Se &ee +um)'#* en"%n+es '13(  R >>>  Ra

P(*( >ue se( +%ns#&e*(&( &es)*e+#('e '( )%"en+#( &#s#)(&( en e' (m)e*-me"*% "(m#=n &ee*á +um)'#*se '( +%n&#+#/n '13(. I6.

Marco 7onceptual. Resistencia2.- Se

&en%m#n( *es#s"en+#( &e' +%n&u+"%* ( '( *(ue *e('#ue e' +%+#en"e &e '( &#e*en+#( &e )%"en+#(' )%* '( #n"ens#&(& se m(n"#ene +%ns"(n"e. L( 'e3 &e )*%)%*+#%n('#&(& en"*e '( &#e*en+#( &e )%"en+#(' ()'#+(&( 3 '( #n"ens#&(& >ue +#*+u'( )%* e' +%n&u+"%* +%ns"#"u3e '( 'e3 &e O:m  R

2

=

V  *

− V A

 I 

 D%*(&%; A'%ns% D#++#%n(*#% en+#+'%)=&#+% un#$e*s('; Págs. 07 9 072

909

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

A' se* '( *es#s"en+#( e' +%+#en"e en"*e un( "ens#/n 3 un( #n"ens#&(&; su /*mu'( &#mens#%n(' es [ R] = [ , ] M [ +] 2 M [ T ]

−4

M [ I ]

−2

en e' s#s"em( #n"e*n(+#%n('; '( un#&(& &e *es#s"en+#( se &en%m#n( %:m#% u %:m ?s-m%'%; @ s#en&% un %:m#% '( *es#s"en+#( &e un +%n&u+"%* >ue (!% un( &#e*en+#( &e )%"en+#(' &e un $%'"#% )e*m#"e e' )(s% &e un (m)e*#%. L(s *es#s"en+#(s se em)'e(n )(*( *egu'(* '( +(n"#&(& &e +%**#en"e >ue +#*+u'( )%* +(&( *(m( &e un +#*+u#"%. En '%s +#*+u#"%s &e +%**#en"e +%n"#nu( '%s *es#s"%*es se +%ns#&e*(n +%m% *es#s"en+#(s )u*(s; )e*% en '%s &e +%**#en"e ('"e*n( :(3 >ue "ene* en +uen"( >ue; (&emás &e *es#s"en+#( ;un *es#s"%* )*esen"( un( #n&u+"(n+#( ?+(*(+"e*-s"#+( &e '(s  %#n(s@ 3 un( +()(+#&(& ?+(*(+"e*-s"#+( &e '%s +%n&ens(&%*es@ en se*#e; '(s +u('es &een *e&u+#*se (' m-n#m% &e %*m( >ue n% se ('"e*en

sens#'emen"e '(s

+(*(+"e*-s"#+(s &e *es#s"en+#( )u*( &e' *es#s"%*. L(s *es#s"en+#(s )ue&en se* #!(s ? $('%* #n$(*#('e@; (!us"('es? $('%* (!us"('e +%n e' +#*+u#"% 3( m%n"(&%@ 3 $(*#('es? +u3% $('%* )ue&e +(m#(*se s#em)*e >ue se &esee@. En e' +(s% &e'(s *es#s"en+#(s #!(s; '(s más +%munes &e '(s +u('es sue'en se* &e +(*/n +%n +u#e*"( &e +e*ám#+(; su $('%* n%m#n(' 3 su "%'e*(n+#( ?&#e*en+#( má1#m( (&m#"#&( en"*e e' $('%* *e(' 3 e' n%m#n(' &e '( *es#s"en+#(@ se sue'en #n&#+(* me&#(n"e  (n&(s &e +%'%*es. C%ns#&e*(n&% '( )*#me*( (n&( +%m% '( más )*/1#m( (' e1"*em% &e' *es#s"%*; s# =s"e ''e$( #m)*es(s +u("*% (n&(s; '(s &%s )*#me*(s #n&#+(n +#*(s s#gn##+("#$(s &e' $('%* &e '( *es#s"en+#(; '( "e*+e*(; e' (+"%* )%* e' >ue es(s +#*(s &een mu'"#)'#+(*se; 3 '( +u(*"(; '( "%'e*(n+#(. En e' +(s% &e '%s *es#s"%*es &e +#n+%  (n&(s; '(s "*es )*#me*(s #n&#+(n +#*(s s#gn##+("#$(s; 3 '( +u(*"( 3 '( >u#n"( e' (+"%*  mu'"#)'#+(&%* 3 '( "%'e*(n+#(. Resistividad.-

L( *es#s"en+#( &e un +%n&u+"%*es m(3%* +u(n"% más '(*g% es e'

*e+%**#&%; es &e+#*; >ue (umen"( +%n '( '%ng#"u& ' &e' +%n&u+"%*; 3 es men%* +u(n"% m(3%* es '( se++#/n S; 3( >ue ( m(3%* se++#/n más (m)'#( es '( ($en#&( )%* '( >ue se  )ue&en +#*+u'(* '%s e'e+"*%nes. P%* su)ues"%; "(m#=n &e)en&e &e' m("e*#(' &e >ue es"á :e+:% e' +%n&u+"%*. E1)e*#men"('men"e se +%m)*ue( >ue 99

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

 R

=

 p

l  - 

&%n&e ) es '( *es#s"#$#&(& &e' +%n&u+"%*; +(*(+"e*-s"#+( >ue &e)en&e &e' m("e*#(' ' es '( '%ng#"u& &e' +%n&u+"%* 3 S; su se++#/n . &e (+ue*&% +%n es"( /*mu'(; '( *es#s"#$#&(&es m#&e en %:m#%s )%* me"*% ?m@. En %+(s#%nes; en 'ug(* &e '( *es#s"en+#( )ue&e #n"e*es(* +%ns#&e*(* su $('%* #n$e*s%; >ue se &en%m#n( +%n&u+"(n+#( 3 se m#&e en s#emens?S@; s#en&% ,S,9,; &e (:- >ue :(s"( :(+e un%s (%s se &en%m#n(( %:m ( es"( un#&(&. Aná'%g(men"e. E' $('%*  #n$e*s% &e '( *es#s"#$#&(& se &en%m#n( +%n&u+"#$#&(& 3 se m#&e en s#emensKm. En '%s +%n&u+"%*es; '( *es#s"#$#&(& $(*#( &e %*m( )*á+"#+(men"e '#ne(' +%n '( "em)e*("u*(; (umen"(n&% +%n =s"(; 3( >ue +u(n"% más ('"( se( '( "em)e*("u*( m(3%*  se*á '( (g#"(+#/n "=*m#+( 3; )%* '% "(n"%; m(3%* se*á e' nme*% &e +:%>ues &e '%s e'e+"*%nes +%n '%s #%nes me"á'#+%s #!%s; s#en&% es"%s +:%>ues '%s +(us(n"es &e '( *es#s"en+#( ( '( +%n&u++#/n . P%&*em%s )ues es+*##*  p

=  p 

(, +  ) M t )

&%n&e Q es '( *es#s"#$#&(& ( '( "em)e*("u*( "; ); '( *es#s"#$#&(& ( C 3 ; es ''(m(&% +%e#+#en"e &e "em)e*("u*(; >ue; en"*e (m)'#%s '-m#"es +%ns#&e*(*se +%ns"(n"e. 6.

,rocedimiento eperimental.

P(*( es"( )*á+"#+(; se us(*%n '%s s#gu#en"es m("e*#('es • • • • • •

T('e*% &e *es#s"en+#(s Am)e*-me"*% V%'"-me"*% Fuen"e &e $%'"(!e C('es &e +%ne1#/n Tes"e* 

9 , 9

&e "em)e*("u*(; )ue&e

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

En es"( )*á+"#+(; us(m%s &%s +%ne1#%nes &#s"#n"(s; )(*( '( )*#me*(; +%ne+"(m%s en  )(*('e'% e' $%'"-me"*%; 3 ue*( &e es"( +%ne1#/n +%ne+"(m%s un (m)e*-me"*%; en"%n+es  )(*( me&#* e' $%'"(!e &e '( *es#s"en+#(; 3 'e u#m%s &(n&% &#e*en"e $%'"(!e; )(*( me&#*  e' (m)e*(!e >ue n%s &(( ( &#e*en"e $%'"(!e. P(*( e' segun&% +(s%; +%ne+"(m%s (' (m)e*-me"*% en se*#e +%n '( *es#s"en+#(; es &e+#*; ( (' +%ne1#/n (n"e*#%*; )us#m%s e' (m)e*-me"*% en se*#e. En"%n+es me&#m%s &#e*en"es $%'"(!es 3 s(+(m%s '(s #n"ens#&(&es &e +(&( $%'"(!e >ue (**%!(( e' (m)e*-me"*% 6I.

nálisis " tratamiento de datos -

C%ns"*u#* '( g*á#+( V en un+#/n &e I +%n '%s $('%*es %"en#&%s )(*( (m%s +#*+u#"%s. 7ircuito 1

9:

Tabla 1 8atos obtenidos en laboratorio 6 '6oltios(

I 'amp(

, 2 4 7 5 J

2.82 7.28 J.,7 0., ,. ,,.

.7 .8 ., .,4 .,8 .2

&uente; E'(%*(+#/n )*%)#(

9 G*á#+( V $s. I

9 ,, 9

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

Gráfica 1 - V vs I    % 15   s   $    i    t    &   $ 10   v    !   e    ' 5   a    t    &   $    V 0

0

0.05

0.1

0.15

0.2

0.25

Intensia !a"#eri$s% &uente; E'(%*(+#/n )*%)#(

-

A!us"(n&% '( *e+"( Es"( *e+"( se )ue&e (seme!(* +%n un( *e+"( +%n #n"e*se++#/n nu'( ?3  B1@; en"%n+es (' ()'#+(* *eg*es#/n '#ne('; se )ue&e en+%n"*(* e' $('%* &e B; >ue +%**es)%n&e (' $('%* &e '( *es#s"en+#( A!us"(n&% )%* e' m="%&% &e m-n#m%s +u(&*(&%s  * =

∑  !) ∑ ! 2

en"%n+es B *esu'"( J.22 ς e' #n"e*$('% &e +%n#(nue '%s $('%*es es"u$#e*%n &en"*% &e '%s +%ns#&e*(&%s )(*( >ue se )u&#e*(n ee+"u(*  '(s me&#+#%nes +%**es)%n&#en"es; )%* es% n% '(s "%m(m%s en +uen"(. O"*% (+"%* >ue )u&% :(e* #n'u#&% es '( +%ne1#/n; )%*>ue ('gun%s +('es es"((n en m(' es"(&%; '% >ue n%s )u&% :(+e* $(*#(* '( me&#+#/n; (un>ue '%s "*("(m%s &e +%**eg#*;  )u&% :(e* ('gn e**%* en es( )(*"e. F#n('men"e; )u&#m%s &(*n%s +uen"( &e >ue '( 'e3 &e O:m; se $e*##+( e1)e*#men"('men"e; )%*>ue (' :(+e* '(s g*á#+(s; 3 (!us"(*'(s; "e &(s +uen"( &e >ue ee+"#$(men"e '( *e'(+#/n en"*e $%'"(!e e #n"ens#&(& es '#ne('; 3 >ue )(*( $%'$e* es% un( #gu('&(&; se 'e ()'#+( un( +%ns"(n"e 3 es( +%ns"(n"e es !us"(men"e e' $('%* &e '(

9 ,7 9

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

*es#s"en+#( &e' m("e*#(' en e' >ue es ()'#+(&( '( #n"ens#&(&; en"%n+es '%g*(m%s $e*##+(*  '( e+u(+#/n &e O:m ?Le3 &e O:m@; es $e*&(&e*(.

6III. ue %*e+e &##+u'"(& (' )(s% &e '( +%**#en"e e'=+"*#+( 3 +%m% +%nse+uen+#( se +('#en"(. Cu('>u#e*( >ue se( '( &#*e++#/n &e '( 4

 em(ns3; Se(*s W Y%ung; F*ee&m(n; F-s#+( Un#$e*s#"(*#( n%$en( e&#+#/n; Págs. 05 9 0,,

9 ,5 9

UNIVERSIDAD MAYOR DE SAN ANDRES FACULTAD DE INGENIERÍA FÍSICA BASICA II

LEY DE OHM

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