Question

A p.d of 20V is applied across two resistors of 4ohm and 6ohm connected in series. Determine the point across the 6ohm resistors if the total circuit current is 2A.

a)1.0V b)2.0V c)3.3V d)12.0V​

Answer 1

D) 12.0 V

Step-by-step explanation:

When resistors are connected in series, the total resistance is the sum of the individual resistances. Therefore, the total resistance in this circuit is:

R_total = 4 ohm + 6 ohm = 10 ohm

According to Ohm's Law, the voltage drop across a resistor is equal to the product of the current flowing through the resistor and the resistance of the resistor:

V = I * R

Therefore, the current flowing through the 6 ohm resistor is:

I_6ohm = V_6ohm / R_6ohm

where V_6ohm is the voltage drop across the 6 ohm resistor.

To find V_6ohm, we need to use Kirchhoff's Voltage Law (KVL), which states that the sum of the voltages around a closed loop in a circuit is zero. In this case, we can apply KVL to the loop that includes the 4 ohm resistor, the 6 ohm resistor, and the voltage source:

V_source - V_4ohm - V_6ohm = 0

Substituting the given values, we get:

20 V - 2 A * 4 ohm - 2 A * 6 ohm = 0

Solving for the current, we get:

I = 2 A

Therefore, the current flowing through the 6 ohm resistor is also 2 A:

I_6ohm= I = 2 A

Now we can use Ohm's Law to find V_6ohm:

V_6ohm = I_6ohm * R_6ohm

Substituting the given values, we get:

V_6ohm = 2 A * 6 ohm = 12 V

Therefore, the voltage drop across the 6 ohm resistor is 12 V. The answer is option (d) 12.0V.