A current of 2 A, passing through a conductor produces 80 J of heat in 10 seconds. The resistance of the conductor in ohm is

Question

In a meter bridge experiment, a resistance of \( 10 \, \Omega \) is balanced by a resistance \( X \) with a balance point at \( 40 \, \mathrm{cm} \). What is the value of \( X \)?

Answer 1

To determine the resistance of the conductor, we will use the formula for electrical power and the relationship between power, current, and resistance.

According to Joule’s Law, the heat produced by a current passing through a conductor is given by:

H = I^2 \cdot R \cdot t

Where:

H = Heat produced (in joules)
I = Current (in amperes)
R = Resistance (in ohms)
t = Time (in seconds)

Given:

Heat produced, H = 80 \, \text{J}
Current, I = 2 \, \text{A}
Time, t = 10 \, \text{s}

We need to find the resistance R.

Substitute the given values into the formula:

80 = (2)^2 \cdot R \cdot 10

Simplifying the equation gives:

80 = 4 \cdot R \cdot 10

80 = 40R

Solving for R gives:

R = \frac{80}{40} = 2 \, \Omega

Therefore, the resistance of the conductor is 2 ohms.

Hence, the correct option is 2.

Answer 2