Capacitor Charging /Discharging

In this experiment we will be dealing with a circuit that will be charging and discharging a capacitor. the charging of the capacitor is governed by the Capacitor, the charging and discharging resistor,

 

we will need to build a circuit where we are utilizing a

12 Volts Voltage source.

charging time =20seconds

discharging time = 2 sec..

 

here is how we obtained the Capacitor value

 

here is how we obtained the charging Resistance

here is how we obtained the discharging Resistance

 

 

Here is the actual circuit

 

we begin by charging the capacitor and obtaining a final voltage of  10.62 volts

 

 

 

after charging and discharging the capacitor we found that the time for charging was 22.27 seconds was suppose to be 20 seconds . the discharging time was 5.15 seconds where it was suppose to be 2 seconds. also the final voltage across the capacitor was not 12 volts and this was due to the leakage resistance.



PRACTICAL SIGNAL CONDITION

 

 

using an LM35 Electronic temperature sensor. we are told that this electronic device  produces an output voltage of 10mv per each degree Celsius. here is a pictorial depiction of how to connect this temperature sensor.

 

 

 

 

In the U.S, The temperature is read in Fahrenheit. we will do the necessary in order to produce the right reading. This reading will be in degrees Fahrenheit.  we will utilize an op amp connected to the sensor. this circuit will look like this.

 

 

  

in order to find R1 and R2 this is the calculations that were made. Using the two equations we found a resistance ratio. and then picked two resistance that would give that ratio.

 

 we then proceed to find Vref.

 

 during the connection of our circuit we encounter a  problem. the problem was that since our breadboard only allowed for two  voltages, we need a third voltage (Vref going in our circuit). we use a resistance in order to obtain the Vref needed using voltage divider rule this is the R obtained.

 

 

 After all our calculations were done, we then proceed to build our final circuit.

we then obtained the Vf  which in this case is the temperature in degrees Fahrenheit.  6.59 mV(65.9 degrees Fahrenheit) and here is the percent error,

 

 

Overall we found out that our circuit was around 90 percent accurate in transforming degree Celsius to degree Fahrenheit.  

 

 

 

 

 

OPERATIONAL AMPLIFIERS 1

In this lab we will investigate how an op amp amplifies the voltage in order to obtain the voltage required. 

here is a picture of the original problem in the left side we have the sensor and in the right we have the op amp.

we will start this problem by first solving for the resistances in the right side here are the calculations. most of the calculations were done with the restrictions that are applied

we then proceed to solve for the left part of the problem. we also used the restrictions and the values found on the right part of the problem.

we also figured out the resistance by taking in consideration the power

we then proceed to calculate our Ry

after we were done we then proceed to measure our resistances and voltages 

and here was the actual circuit

after measuring here is a table of what we obtained 

 in conclusion we found out that a problem can be easier when broken into several pieces. we also found out that our measurements were not far apart from the theoretical notes. the op amp used was actually helpful in amplifying and inverting the voltage