A small bulb has a resistance of 2 ohm when it is cold. It draws 0.4 ampere current from a source of 4 V and then starts glowing. Calculate the resistance when it is glowing.

Given: Resistance (R _cold) = 2 Ohm

Current (I) = 0.4 Ampere

Voltage (V) = 4 V

The resistance when the bulb is glowing is calculated by using Ohm’s law.

According to Ohm’s law,

V = I x R

Substituting the values in the above equation, we get

R = 4/0.4

R = 10 Ohm

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A small bulb has a resistance of 2 ohm when it is cold. It draws 0.4 ampere current from a source of 4 V and then starts glowing. Calculate the resistance when it is glowing.

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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 ?

3.
This ‘average velocity’ is found be few mm/s for currents in range of a few amperes. How then is current established almost the instant a circuit is closed ?

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Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

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Consider the nuclear reaction \( X \to Y + Z \). Let \( M_x \), \( M_y \), and \( M_z \) be the masses of the three nuclei X, Y, and Z respectively. Then which of the following relations hold true?

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A small bulb has a resistance of 2 ohm when it is cold. It draws 0.4 ampere current from a source of 4 V and then starts glowing. Calculate the resistance when it is glowing.

Related Questions

CBSE CLASS XII Related Questions

1.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 ?

3.This ‘average velocity’ is found be few mm/s for currents in range of a few amperes. How then is current established almost the instant a circuit is closed ?

5.Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

6.Consider the nuclear reaction \( X \to Y + Z \). Let \( M_x \), \( M_y \), and \( M_z \) be the masses of the three nuclei X, Y, and Z respectively. Then which of the following relations hold true?

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

1.
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 ?

3.
This ‘average velocity’ is found be few mm/s for currents in range of a few amperes. How then is current established almost the instant a circuit is closed ?

5.
Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air present between the plates.

6.
Consider the nuclear reaction \( X \to Y + Z \). Let \( M_x \), \( M_y \), and \( M_z \) be the masses of the three nuclei X, Y, and Z respectively. Then which of the following relations hold true?