Prof. Williams 2.17.2020
Properties of Microwaves
Purpose Statement: The purpose of this lab was determining different properties of microwaves. We analyzed the intensity of the wave as we increase the distance between the transmitter and receiver, the angle of incidence and reflection, reflection through a prism and polarization. Then we verified the recorded data, and we were able to verify them with the proper formula for each property.
V. 1.
CALCULATIONS Complete the graphs for intensity vs. distance and determine the mathematical relationship
Intenisty (mA) vs. Distance (cm) Graph
12
y = 72.961e-0.048x
10
8 Intensity (mA) 2 0 0
10
20
30
40 50 Distance (cm)
60
70
80
90
2.
Determine the relationship for the angle of reflection as a function of the angle of incidence. 0i=0r Perpendicular to surface Incident ray Reflected ray
0
e
Surface
3. Determine the index of refraction of the styrene pellets. n1 sin 01 = n2 sin 02 n = 1.00 Refracted 1 * sin(20) = nsin (10) Beam sin(20) 0.342020143 1.97 sin(10) 0.173648177 ncident Beam Normal t Boundary of Refraction
=10 90 170 90.7020=820 92.91+8201030
4.
Determine the relationship for the intensity of the wave and the angle of the polarizer.
Intensity (mA) as a Function of Polarizer Angle
10
8 (mA) Intensity 2
0
20
40
60
80
100
Polarizer's Angle (degree)
V. CONCLUSIONS/QUESTIONS
1.Answer the questions in each section.
Reflection: 1.What relationship holds between the angle of incidence and the angle of reflection? Does this relationship hold for all angles of incidence?
The angle of incidence is equal to the angle of reflection with respect to the normal from the point of incidence on the plane. 0i=0r This relationship does hold for all angles of incidence theoretically. However, when the angle of incidence in this experiment was above 60, the 0; was not exactly equal to 0, because at various angle settings the receiver detected both the reflected wave and the wave coming directly from the transmitter.
2. In measuring the angle of reflection, you measured the angle at which a maximum meter reading was found. Can you explain why some of the wave reflected into different angles? How does this affect your answer to question 1?
Some of the wave reflected into different angles because at various angle settings, which in the case of this experiment was between 60-90 the receiver detected both the reflected wave and the wave coming directly from the transmitter. This would be leading to results that are not correct. As it can be seen in the data table for the reflection section, the incidence angles between 60-90 did not obey the equation O: = 0r. However, if it were a perfect plane wave, the relationship Would hold.
3. Ideally you would perform this experiment with a perfect plane wave, so that all the Transmitter radiation strikes the Reflector at the same angle of incidence. Is the microwave from the Transmitter a perfect plane wave (Consider how you could test this)? Would you expect