Four Steps to Drawing Ray Diagrams Plane mirror ray diagrams show how light travels from an object to the mirror to an eye in order for the
eye to view the image of the object. There are four steps to the construction of a ray diagram.
i.
Draw the image of the object.
ii. Pick one extreme on the image of the object and draw the reflected ray that will travel to the eye
as the eye sights at this point.
iii. Draw the incident ray for light traveling from the corresponding extreme on the object to the
mirror.
iv. Repeat steps ii and iii for all other extremities on the object.
Locating Images
1. Locate all of the images for the following objects (labeled "o") as produced by the mirror (labeled
"m"). Consider steps 1 and 2 above.
b.
C.
.0
B
d.
f.
0
m
m

Fft review: linspace, fs, fftshift, nfft 1. generate one second of a cosine of w,-10hz sampled at f, = 100hz and assign it to x. define a tt as your time axis 2. take 64 points fft. 3. as you remember, the dft (which the fft implements) computes n samples of s2t where k-0,1,2, n -1. plot the magnitude of this 64-points fft at range 0 to 63, what do you think of this graph? 4â·to get the x-axis into a hz-frequency form, plot this 64-points fft between-50 to 50 (the 100hz sampling rate) and have n-points between them. 5. according to your figure, what frequency is this cosine wave at? 6. remember that the fft is evaluating from 0 to 2ď€. we are used to viewing graphs from-ď€ to ď€. therefore, you need to shift your graph. 7. now according to your shifted graph. what frequency is this at? 8. note that the spikes have long drop-offs? try a 1024-point dft. note that the peak is closer to 10 and the drop-off is quicker. although, now sidelobes are an issue

As a car drives with its tires rolling freely without any slippage, the type of friction acting between the tires and the road is 100) a) static friction. b) kinetic friction. c) a combination of static and kinetic friction. d) neither static nor kinetic friction, but some other type of friction. e) it is impossible to tell what type of friction acts in this situation.

Four friends, a, b, c, and d are standing varying distances away from a speaker which is producing sound waves.