Problem 5.224

In the Fizeau experiment on measurement of the velocity of light the distance between the gear wheel and the mirror is \(l\) \(=7.0 \mathrm{~km},\) the number of teeth is \(z=720 .\) Two successive disappear- ances of light are observed at the following rotation velocities of the wheel: \(n_{1}=283\) rps and \(n_{2}=313\) rps. Find the velocity of light.