When a 12V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit, determine resistance.

A current of 2.5 mA passes in the circuit because a 12 V battery has been connected with an unknown resistance.

V = 12 V

I = 2.5 mA = 2.5 × 10⁻³ A

Formula Used

Considering R as resistance.

If every physical condition remain constant, Ohm's law claims that the voltage across a conductor will be directly proportional to the current flowing through it. The resistance (R) of a resistor is expressed by Ohm's law.

V = IR

Calculation of Resistance

Now, by inserting the value of V and I in Ohm's law, we can obtain,

12 = 2.5 × 10⁻³ R

⇒ R = 4.8 × 10³ Ω

Thus, the resistor's resistance is 4.8 × 10³ Ω.

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When a 12V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit, determine resistance.

Formula Used

Calculation of Resistance

Related Questions

CBSE CLASS XII Related Questions

2.
Two metal spheres of radii $r_1$ and $r_2$ ($> r_1$) having charges $q_1$ and $q_2$ respectively kept in air, are brought in contact. Which of the following statements is not correct ?

4.
The resistance of a metal wire at \( 20^\circ \text{C} \) is \( 1.05 \, \Omega \) and at \( 100^\circ \text{C} \) is \( 1.38 \, \Omega \). Determine the temperature coefficient of resistivity of this metal.

Similar Physics Concepts

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When a 12V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit, determine resistance.

Formula Used

Calculation of Resistance

Related Questions

CBSE CLASS XII Related Questions

2.Two metal spheres of radii $r_1$ and $r_2$ ($> r_1$) having charges $q_1$ and $q_2$ respectively kept in air, are brought in contact. Which of the following statements is not correct ?

4. The resistance of a metal wire at \( 20^\circ \text{C} \) is \( 1.05 \, \Omega \) and at \( 100^\circ \text{C} \) is \( 1.38 \, \Omega \). Determine the temperature coefficient of resistivity of this metal.

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

2.
Two metal spheres of radii $r_1$ and $r_2$ ($> r_1$) having charges $q_1$ and $q_2$ respectively kept in air, are brought in contact. Which of the following statements is not correct ?

4.
The resistance of a metal wire at \( 20^\circ \text{C} \) is \( 1.05 \, \Omega \) and at \( 100^\circ \text{C} \) is \( 1.38 \, \Omega \). Determine the temperature coefficient of resistivity of this metal.