A 5 omhs resistor is connected in series with an unknown resistor. The current flowing in the circuit is found to be 0.2A when a voltage of 40V is applied. Find the value of the unknown resistance? ?

To find the value of the unknown resistance, we can use Ohm's Law, which states that V = IR, where V is the voltage, I is the current, and R is the resistance.

In this case, we know that the total resistance in the circuit is the sum of the 5 ohm resistor and the unknown resistor, so we can write:

Total resistance = 5 ohms + unknown resistance

We also know that the current flowing in the circuit is 0.2A and the voltage applied is 40V. So we can write:

40V = (5 ohms + unknown resistance) * 0.2A

Solving for the unknown resistance:

40V = (5 ohms + unknown resistance) * 0.2A
40V = 1 ohm + 0.2A * unknown resistance
40V = 1 + 0.2 * unknown resistance
39V = 0.2 * unknown resistance
unknown resistance = 39V / 0.2
unknown resistance = 195 ohms

Therefore, the value of the unknown resistance is 195 ohms.

Applying Ohm's law, we have:
Total resistance = Voltage / Current
Total resistance = 40V / 0.2A = 200 ohms

Since the 5 ohms resistor is in series with the unknown resistor, the total resistance is the sum of the two resistances.
Let the unknown resistance be R ohms.
Therefore, R + 5 ohms = 200 ohms
R = 200 ohms - 5 ohms
R = 195 ohms

Hence, the value of the unknown resistance is 195 ohms.