Question

can you plz help me​

Answer 1

FORMULA :

• $\sf V \: = \: IR$
• $\sf R \: = \: \dfrac {V}{I}$
• $\sf I \: = \: \dfrac {V}{R}$
• $\sf \dfrac {1}{R} \: = \: \dfrac {1}{R_1} \: + \: \dfrac {1}{R_2} .......$

SOLUTION :

We know that,

$\sf \dfrac {1}{R} = \dfrac {1}{R_1} + \dfrac {1}{R_2} + .......$

$\sf \dfrac {5+3}{5 \times 3} \: = \: \dfrac {8}{15}$

$\therefore \sf R = \dfrac {15}{8}$

Now,

$\sf Current, \: I \: = \: \dfrac {V}{R}$

Put the values in the above formula,

→ $\sf\dfrac{\dfrac{2}{15}}{8}$

→ $\sf \dfrac {16}{15}$

Now, $\sf V \: = \: \dfrac {I}{R}$

→ $\sf \dfrac {1}{x} + \dfrac {1}{6}$

→ $\sf \dfrac {x + 6}{x \times 6}$

→ $\sf \dfrac {x + 6}{6x}$

→ $\sf \dfrac {6x}{x + 6}$

Here, V = IR.

$\sf 2 \: = \: \dfrac {16}{15} \times \dfrac {6x}{x + 6}$

→ $\sf 15(x + 6) \: = \: 8(6x)$

Multiply the brackets.

we get,

→ $15x \: + \: 90 \: = \: 48x$

→ $\sf 90 \: = \: 33x$

→ $\sf x \: = \: \dfrac {90}{33}$

→ $\sf x \: = \: \dfrac {30}{11} \Omega$