Question

answer question 69,70

Answer 1

hey mate !!!

here is your answer !!!

potential difference is => 20 v

resistance => 20 ohm .

v = I R =>

20V = I *20ohm

=> I = 1 ampare

Heat generated in 1 sec =>

H= I ² *R *T

=> 1² *20 * 1 sec

=> 20 j

hence Option number D is correct !!!

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now , your second question :-


AB = 1/ 3 Ohm + 1/3 ohm + 1/3 ohm + 3 ohm

=> 10 ohm

hence , option number B is correct !!!




hope it helps you dear !!!

thanks

Answer 2

69 ) 

-> POTENTIAL DIFFERENCE IN A PARALLEL CIRCUIT DOESN'T CHANGE.

$Here \ R_{eq} = \frac{R/2}{2} = \frac{R}{4}$

=> Total Current = ( V / R ) = ( V / ( R / 4 ) ) = ( 4V / R )
=> Option C is correct !
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70 ) 
-> Simplifying the Circuit further, by naming the potentials : 
---> The potential at the circumference is all same -> " B "
---> The potential at the center is -> "C"
---> The final potential -> "A" 

Check out the given Simplification to further solve the problem :

[tex]R_{eq} = [ \frac{1}{3R} + \frac{1}{3R} + \frac{1}{3R} ]^{-1} + R \\ \\ =\ \textgreater \ R_{eq} = R + R = 2R[/tex]

--> Option B is correct !