Day 9

In the beginning of the lab, we go to find the power source when it is ideal and not ideal. When we are going to do ideal, the current 0.0455 A, and the power is 1, so the power should be P=VI = 0.0455W. However, when we are going to calculate, we find the current always be lower than 0.0455, it shows there is a other resistor in the inside of power source. And its power is 22/(22+Rs)^2 W.

In the 22 ohm resistor, its real value is 22.4ohm.

Because there is a inside resistor, when we want to get 1V, it only shows 0.994V. However, we increase it to 1V

measure the output voltage is 0.980V.

 We use a 39ohm resistor, but its true value is 38.8 ohm, and we found its voltage is 0.993V

 

In the lab, we calculate two resistor 22.4ohm and 38.8ohm, and its voltage is 0.980V and 0.993V. after the calculate, we find that the inside resistor is 0.457ohm and 0.273ohm.

In this lab, first when we are doing pre-lab, we calculate power on a 2.2K ohm resistor. And its power 2.84*10^-3W

In the experiment, we choose two 2.2k ohm resistors, the real value is 2.16k ohm.

 We measure that the voltage on the resistor is 2.48 V. So we calculate the power is 2.847*10^-3 W. its percent difference is  -0.246 %.