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a 15 ohms bell and an 8.0 ohms lamp are connected in parallel and placed across a potential difference of 42-V.
what is the equivalent resistance of the circuit?
what is the current in the circuit?
what is the current through each resistor?

Respuesta :

Answer:

The current through the bell is approximately 2.8 A and the current through the lamp is approximately 5.25 A.

Explanation:

When resistors are connected in parallel, the reciprocal of the equivalent resistance ( [tex]R_{eq}[/tex] ) is equal to the sum of the reciprocals of the individual resistances. The formula for resistances in parallel is given by:

[tex]\frac{1}{R_{eq}} = \frac{1}{R_{1}} + \frac{1}{R_{2}} + ... + \frac{1}{R_{n}}[/tex]

In this case, with a 15-ohm bell ( [tex]R_{1}[/tex] ​) and an 8.0-ohm lamp ( [tex]R_{2}[/tex] ​), the equivalent resistance ( [tex]R_{eq}[/tex] ​) can be calculated as follows:

[tex]\frac{1}{R_{eq}} = \frac{1}{15} + \frac{1}{8}[/tex]

Now, find the common denominator:

[tex]\frac{1}{R_{eq}} = \frac{8}{120} + \frac{15}{120} = \frac{23}{120}[/tex]

Now, take the reciprocal of both sides:

[tex]\frac{1}{R_{eq}} = \frac{120}{23}[/tex]

[tex]\frac{1}{R_{eq}}[/tex] ≈ 5.217Ω

Now, to find the current (II) in the circuit, you can use Ohm's Law ( [tex]I = \frac{V}{R_{eq}}[/tex] ​):

[tex]I = \frac{42}{5.217}[/tex]

I ≈ 8.06 A

Finally, to find the current through each resistor in a parallel circuit, you can use Ohm's Law ( [tex]I_{i} = \frac{V}{R_{i}}[/tex] ​):

For the bell ( [tex]I_{bell}[/tex] ​):

[tex]I_{bell} = \frac{42}{15}[/tex]

[tex]I_{bell}[/tex] ≈ 2.8 A

For the lamp ( [tex]I_{lamp}[/tex] ):

[tex]I_{lamp} = \frac{42}{8}[/tex]

[tex]I_{lamp}[/tex] ≈ 5.25 A