How will the amount of heat that is released in a conductor change if the resistance
How will the amount of heat that is released in a conductor change if the resistance is doubled at a constant current strength?
Given:
I1 = I2 = I – the current does not change;
R2 = 2 * R1 – the conductor resistance was doubled.
It is required to determine Q2 / Q1 – how the amount of heat that is released in the conductor will change.
The amount of released heat in the first case will be equal to:
Q1 = W1 * t = U1 * I1 * t = I1 * I1 * R1 * t = I1 ^ 2 * R1 * t = I ^ 2 * R1 * t, where t is a certain period of time.
The amount of released heat in the second case will be equal to:
Q2 = W2 * t = U ^ 2 * I ^ 2 * t = I ^ 2 * I ^ 2 * R ^ 2 * t = I2 ^ 2 * R ^ 2 * t = I ^ 2 * R ^ 2 * t.
Then:
Q2 / Q1 = (I ^ 2 * R ^ 2 * t) / (I ^ 2 * R1 * t) = R ^ 2 / R1 = (2 * R1) / R1 = 2, that is, it will increase by 2 times.
Answer: when the resistance of the conductor doubles, the amount of heat released will also double.