Question

E=6B R=2ом R внешнее =8Вт найти I к.з

Answer 1

При КЗ отсутствует внешнее сопротивление (к тому же сопротивление не измеряется в ваттах!!!),
поэтому:
Iкз = E / r = 6 / 2 = 3 А

Answer 2

Для всей цепи E=I*(R+r)
найдем ток цепи I=P/E=8/6A
Рассчитаем внутреннее сопротивление источника
R+r=E/I
r=(E/I)-R=6/(6/8)=8Ом
Тогда ток короткого замыкания 
Iz=E/r=6/8=3/4=0.75A

Answer 3

To find the current (I) through the circuit, you can use Ohm's Law, which states:

$V = I \cdot R$

where: V = Voltage (in volts) I = Current (in amperes) R = Resistance (in ohms)

In this case, we have the following information:

• E = 6 volts (Voltage across the internal resistance and the external resistance combined)
• R_internal = 2 ohms (Internal resistance)
• P_external = 8 watts (Power dissipated in the external resistance)

To find the total resistance (R_total) in the circuit, we can use the power formula:

$P = \frac{V^2}{R}$

where: P = Power (in watts) V = Voltage (in volts) R = Resistance (in ohms)

For the external resistance:

$P_{\text{external}} = \frac{E^2}{R_{\text{external}}}$

Now we can rearrange the formula to solve for the external resistance (R_external):

$R_{\text{external}} = \frac{E^2}{P_{\text{external}}}$

Substitute the given values:

$R_{\text{external}} = \frac{6^2}{8} = \frac{36}{8} = 4.5 \text{ ohms}$

Now, to find the total resistance (R_total) in the circuit:

$R_{\text{total}} = R_{\text{internal}} + R_{\text{external}} = 2 \text{ ohms} + 4.5 \text{ ohms} = 6.5 \text{ ohms}$

Finally, we can use Ohm's Law to find the current (I) through the circuit:

$I = \frac{V}{R_{\text{total}}} = \frac{E}{R_{\text{total}}} = \frac{6 \text{ volts}}{6.5 \text{ ohms}} \approx 0.923 \text{ amperes}$

Therefore, the current through the circuit is approximately 0.923 amperes.