Given
angular frequency ω=3313 rev/min=1003×160 rev/s
ω=2×227×1003×160=3.5 rad/s
For coin to revolve with the record, the force of friction must be enough to provide necessary centripetal force,
i.e.,
mv2R≤μmg⇒mω2R≤μmg
⇒R≤μgω2⇒0.15×10(3.5)2=0.12 m or 12 cm
The coin should be maximum 12 cm from the centre to revolve with the disc. Hence, the coin placed at 4 cm from centre will revolve with the disc.