Mike is a DJ in a famous dance club near Denver, Colorado USA. His job is to pla
ID: 1621688 • Letter: M
Question
Mike is a DJ in a famous dance club near Denver, Colorado USA. His job is to play audience favorite songs on demand provided as a list. In order to accomplish his tasks he has to be efficient while changing a song and for this he sometimes practices at his home as well. One day his brother asked him how you control duration of songs and how different songs are played inside the player. Mike is a DJ and doesn’t know science, he just by practice know how to play the songs on demand, so is unable to answer the questions. If you were the DJ how you would answer these questions provided you know that on a standard CD the audio information is stored in a series of pits and flat areas on the surface of the disc. The cd players are equipped with the laser pointer and when CD rotates inside the player, it targets these pits and falls to read the different songs. The standard CD comes with inner and outer radius 23 mm and 58 mm respectively. Being physics students you know the Newton’s law of rotation and the relationship between rotational and linear variables.
Once you have answered the above question can you estimate the total number of songs that can be fit on this standard CD also how rotational parameters can be used to determine the duration of the song?
Explanation / Answer
ANS. Most CD spins with constant linear velocity. The angular velocity changes so that data transfer rate remains same.the cd spins at 9608.4 radian per second at the inner most starting edge and slow down 3956.4 radian per second for the outer most edge.
the total length of the track of cd is 6002536 mm.