DVD A DVD player (or a CD-ROM reader) works by bouncing a laser off the surface of the
DVD, which acts like a mirror. An emitter sends out the light, which bounces off the DVD
and then is detected by a sensor. The diagram at right shows a DVD held parallel to the
surface of the DVD player, on wlich an emitter and a sensor are mounted.
Emitter
Sensor
DVD
a. The laser is supposed to bounce off the DVD at a 64° angle as shown in the diagram
above. For the laser to go directly into the sensor, at what angle does the emitter need
to send the laser beam? In other words, what does the measure of angle x have to
be? Justify your conclusion.
b. The diagram above shows two parts of the laser beam: the one coming out of the
emitter and the one that has bounced off the DVD. What is the angle (Zy) between
these beams? How do you know?