Day 22

Day 21

Magnetic Motors

The photo is a magnetic motor that runs by applying a voltage through the system.  There is a brush that will continuously turn on and of the the current in order to produce a torque in one direction.  The video displays a running a motor with a electronic motor force of 3 volts.  The higher the voltage source the faster the motor spins.

Home made Moter

In order to replicate the motor we utilized the wire given and made it into  circular shape with as many turns as possible.  The more amount of turns it had the greater the force in would produce on the wire.  On the positive receiving end of the wire the entire end was sanded off, however on the end of the wire were the current left, only half of the wire was sanded of to replicate the brush from the electric motor.  As a result this created a ON and OFF switch to produce a constant torque in one direction.

Day 20

Magnetic Fields

 

As an introduction to magnetic fields, we observed the direction at which the fields on a magnet produces with a compass.  It was observed that the magnetic field exist the magnet from the north, or positive side, of the magnet and enters back through the the south side.

The pictures above displays more vivid picture of how the magnetic fields are directed around a magnet.

The following picture displays how the Net Flux on a magnetic field is always zero.  This was observed in class through the demonstration of cutting in half a  magnet multiple times and still keeping positive and negative polarity.

 
Finding the Magnetic field

In this experiment the copper bar was experiencing a current from a voltage source.  As a result the bar obtained force from the magnet.  

The picture below display the magnetic field the magnet produces.  This was obtained by using the formula of the magnetic field with current, kinematics, inertia of the bar and torque.

Day 19

Amplifier

The Circuit above was given to us as a map in order to recreate this on a bread board.

The picture above is our bread board turned into a one transistor amplifier.

After connecting a voltage source and a frequency generator, it produced the wave above on the oscilloscope.

The circuit above was then given to us in order to recreate it on a circuit board in order to create sound on a speaker.

The picture above is our circuit board turned into an amplifier.

After connecting a voltage source and adding an audio input from a phone and an audio output to a speaker sound was produced.  

Day 18

Oscilloscopes 

In this laboratory we wanted to observe the wave behavior of voltage with an oscilloscope. Our voltage source was derived from a frequency generator. We were then able to utilize the oscilloscope to measure the amplitude of each wave in order to determine the voltage.

The picture above is an frequency generator of 96 Hz.  The period was then calculated 0.012 s from the oscilloscope.

 

When the switching the frequency generator to triangular, the oscilloscope produces a triangular wave as shown above.

When switching the frequency generator to square function, the oscilloscope produces a square wave as shown above.

The following video displays how the graph can be enhanced or changed when the dial on voltage measurement is changed.

Oscilliscope with AC or DC power supply.

DC power supply displayed the distorted wave as shown above.  It was determined that the voltage was around 30 mV

The AC power supply displayed a sinusoidal wave as shown in the above picture.  This was expected since in an an AC current the the voltage is alternating positive to negative.  The voltage on this wave was measure to be 15 v and the period t=(8.5*.002)=0.017s, and finally the frequency f=1/t=1/0.017= 58.8Hz.

We set the function generator to 60 Hz and connected it to Channel 1 and the AC transformer to Channel 2.  A Circle was produced from both inputs.  This was because the frequency generator was interacting with the sinusoidal waves of the AC current.

The Mystery Box

The Mystery box was an unknown object that was connected to the oscilloscope.  Each color was connected to each on another in different patterns.  this was done and observed in order to determine what the mystery box was.

The picture above is the wave produce from the black to yellow connections. 

After many observations, each connection made was drawn above along with their periods and voltage.  Even after scrutinizing each wave it was difficult to determine  what the mystery box was.

Day 17

Discharge and Charge of Capacitors

In this experiment, we intended to measure the relationship in the time it takes to charge and discharge a capacitor in an RC-Circuit.  The upper left of the picture above, the diagram in for the the RC-Circuit is displayed. An EMF of 4.5 V was exerted into the circuit which contained a 3.6 kilo ohm resister and capacitor.  The voltage in the system was measured with logger pro as a function of Voltage vs Time in both charging and discharging of the capacitor.  

The picture above displays the graphs of a charging capacitor in blue and a discharging capacitor in red.  It is determined through the curve fit line that the voltage is an exponential function, V=Voe^(1/torr).  It was determined earlier, in the previous picture, that for is equaled to R*C, the resistance times the capacitance.  More importantly torr is a measurement in time of seconds.

Day 16

 Capacitors 

In this experiment, the capacitance was calculated through the Capacitance equivalent formulas for capacitors in series and in parallel.  After calculations the capacitors were than measured.

The following equations display how capacitors are combined with the displayed calculations above.

The HomeMade Capacitor and Dielectric.

In this experiment, we utilized foil paper to act as a capacitor while the paper in-between will act as a dielectric.  The area of the foil paper was kept constant as the thickness of the paper change in each procedure.  We expected the capacitance to decrease as the thickness of our papered dielectric increased.

At different thickness the voltmeter was utilized to help calculate the capacitance.

The above picture is the data we collected of the capacitance in comparison with the change in distance.  After obtaining the capacitance at one point, we were able to calculate the k constant of the material, 3.49.  Our value for k was determined to be true since it fell was fairly close to our accepted value of 3.49.

The graph above shows how capacitance is inversely related to distance.  This can be seen in formula for a capacitor with a dielectric.