# ECET 345 ECET345 Week 1 Lab Solution

ECET 345 Week 1 Lab

1. How does an experimental approximation of an impulse differ from an ideal impulse?

2. A step input is applied to the following circuit at time *t* = 0. What will the output waveform look like? What is the significance of the time constant for the circuit? How will the observed waveform change as the value of capacitor is increased?

3. How does a sine wave differ from a cosine wave?

4. With the knowledge you gained in the theory section, how can an exponentially growing sinusoid be generated? Can a physical system generate an exponentially growing sinusoid?

5. In finance, what does the growth curve of a compound interest savings account look like over time

6. Create a MATLAB code that generates an amplitude modulated (AM) signal with a 1 Hz information frequency and a 100 Hz carrier frequency, with the carrier amplitude equal to 1.0 and the information frequency amplitude equal to 0.9. The general form of an AM signal is

where *A** _{c}* is the amplitude of the carrier,

*A*

*is the amplitude of the information signal, ω*

_{i}*is the frequency of the information signal in radians/second, ω*

_{i}*is the frequency of the carrier signal in radians/second, and*

_{c}*t*is time. Plot the graph over the time period of 0 to 2 seconds.

*Give meaningful labels to the X and Y axis as well as a title to the graph*

*7. Take the signal generated in the previous question and find the signal spectrum using the tools you have learned in earlier labs. Paste the signal spectrum and code below. (Hint: Use the method of finding the signal spectrum of a signal that was shown in Lab 1.) Give meaningful labels to the X and Y axis as well as a title to the graph.*