Question

Вольтметр, подключенный к зажимам источника тока с ЭДС 24 В, показал 18 В,Определите величину тока в цепи и сопротивление источника энергии ,если сопротивление внешней цепи 9Ом.Решите пожалуйста задачу

Answer 1

I=E/(R+r)
I=U/R=18/9=2 A
E/(R+r)=U/R
r=E*R/U-R=(24*9/18)-9=3 Ом

Answer 2

Problem Analysis

We are given the following information: - The voltmeter connected to the terminals of a current source with an electromotive force (EMF) of 24 V reads 18 V. - The resistance of the external circuit is 9 Ω.

We need to determine the current in the circuit and the resistance of the energy source.

Solution

To solve this problem, we can use Ohm's Law and Kirchhoff's laws.

According to Ohm's Law, the current (I) in a circuit is equal to the voltage (V) divided by the resistance (R). Mathematically, this can be expressed as:

I = V / R

In this case, the voltage (V) is the difference between the EMF of the source (24 V) and the reading on the voltmeter (18 V). Therefore, the voltage across the external circuit is:

V = 24 V - 18 V = 6 V

Substituting the values into Ohm's Law, we can calculate the current (I) in the circuit:

I = 6 V / 9 Ω = 2/3 A ≈ 0.67 A

So, the current in the circuit is approximately 0.67 A.

To find the resistance of the energy source, we can use Kirchhoff's laws. Kirchhoff's laws state that the sum of the voltages in a closed loop is zero and the sum of the currents at a junction is zero.

In this case, the voltage across the external circuit is 6 V, and the current in the circuit is 0.67 A. Therefore, the resistance of the energy source can be calculated using Ohm's Law:

R_source = V / I = 6 V / 0.67 A ≈ 8.96 Ω

So, the resistance of the energy source is approximately 8.96 Ω.

Answer

The current in the circuit is approximately 0.67 A, and the resistance of the energy source is approximately 8.96 Ω.

Please note that the values are approximate due to rounding.