Physics, asked by Anonymous, 5 months ago

please answer this question ?

Class - 10th
Chapter - electricity

Please don't spam and don't give wrong answer ​

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Answers

Answered by MrNobody78
5

The overall current needed = 9A.

The voltage is 12V

Hence by Ohm’s Law V=IR

The resistance for the entire circuit = 12/9Ω = 4/3Ω = R

R1 and R2 are in parallel. Hence, R= \frac{(r1r2)}{r1 + r2}

After putting their values we get r2 = 2Ω

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Answered by suraj5070
610

 \huge{\boxed {\mathbb {QUESTION}}}

a student has two resistors of 2Ω and 3 Ω . he has to put one of them in place of R2 . show in the circuit The current that he needs in the entire circuit is exactly 7A. Show by calculation which of the two resistors she should choose

 \huge{\boxed {\mathbb {ANSWER}}}

 {\boxed {\mathbb {GIVEN}}}

  •  Battery\: source (V) =12V
  •  Total\: current (I) =7A
  •  R_1=4Ω

 {\boxed {\mathbb {TO\:PROVE}}}

  •  Which\:resistor \:choose \:in\:R_2

 {\boxed {\mathbb {SOLUTION}}}

 {\boxed {\boxed {V=IR}}}

  •  V=Battery\: source
  •  I=current
  •  R=resistance

 Substitute\: the\: values

 \implies 12=7\times R

\implies R=\frac{12}{7}

 R_1\:andR_2\:are\:in\:parallel

 \frac{1}{R}=\frac{1}{R_1}+\frac{1}{R_2}

 Substitute \frac{1}{R}=\frac{12}{7}

 \frac{1}{\frac{12}{7}}=\frac{1}{4}+\frac{1}{R_2}

 \implies\frac{1}{12}\times 7=\frac{1}{4}+\frac{1}{R_2}

 \implies\frac{7}{12}=\frac{1}{4}+\frac{1}{R_2}

\implies \frac{7}{12}-\frac{1}{4}=\frac{1}{R_2}

\implies \frac{7-3}{12}=\frac{1}{R_2}

\implies \frac{4}{12}=\frac{1}{R_2}

\implies \frac{1}{3}=\frac{1}{R_2}

 \implies{\boxed {\boxed {R_2=3Ω}}}

 \therefore 3Ω\: resistor\: should\: be \:placed\: in\: R_2

\huge {\boxed {\mathbb {HOPE \:IT \:HELPS \:YOU }}}

_________________________________________

 \huge {\boxed {\mathbb {EXTRA \:INFORMATION}}}

 Formulas

 I=\frac{V} {R}

 V=\frac{W} {Q}

 V=IR

 {\mathbb{\colorbox {orange} {\boxed{\boxed{\boxed{\boxed{\boxed{\colorbox {lime} {\boxed{\boxed{\boxed{\boxed{\boxed{\colorbox {aqua} {@suraj5070}}}}}}}}}}}}}}}

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