Answer:
1063 hits/sec
Explanation:
-Angular velocity of the record is given as:
[tex]\omega= 33 \ rev/min=0.55 \ rev/s[/tex]
-Radius of the record is given as:
[tex]r=11.5\ cm=0.115\ m[/tex]
The linear speed of the record is calculated as:
[tex]v=\omega r\\\\=0.55\times 2\pi \times 0.115\\\\=0.3974 \ m/s[/tex]
The grove bumps are uniformly separated as 0.374 mm(0.000374), the number of hits per second is calculated as:
[tex]hits/s=\frac{v}{us}\\\\=\frac{0.3974}{0.000374}\\\\=1062\ hits/s\approx 1063 \ hits/s[/tex]
Hence, there are 1063 hits/sec