100 identical resistors of 2 Ohm each are connected in parallel. What is their total resistance? What is the total resistance
100 identical resistors of 2 Ohm each are connected in parallel. What is their total resistance? What is the total resistance of two parallel-connected 1 and 2 ohm resistors?
First task.
Given:
R = 2 Ohm is the resistance of the resistors;
n = 100 pieces – the number of resistors.
It is required to find R1 (Ohm) – the total resistance of the resistors.
Since, according to the condition of the problem, the resistors are connected in parallel with each other, then:
1 / R1 = 1 / R + 1 / R + ….. 1 / R;
1 / R1 = n / R;
R1 = R / n = 2/100 = 0.02 Ohm.
Answer: The total resistance of the resistors is 0.02 ohms.
Second task.
Given:
R1 = 1 Ohm – resistance of the first resistor;
R2 = 2 Ohm – the resistance of the second resistor.
It is required to determine the total resistance of the resistors R (Ohm).
Since, according to the condition of the task, the resistors are connected in parallel with each other, then:
1 / R = 1 / R1 + 1 / R2;
1 / R = (R2 + R1) / (R1 * R2);
R = R1 * R2 / (R1 + R2) = 1 * 2 / (1 + 2) = 2/3 = 0.7 ohms.
Answer: The total resistance of the resistors is 0.7 ohms.