Solution:

1. Apparatus:
   • Pulsed laser source
   • Beam splitter
   • Two mirrors (one movable and one fixed)
   • Fast photodetector
   • Oscilloscope
2. Procedure:
   • Set up the laser, beam splitter, mirrors, and photodetector in a vacuum chamber.
   • Pulse the laser and split the beam into two paths using the beam splitter.
   • Reflect the beams off the mirrors and recombine them at the photodetector.
   • Measure the time delay between the pulses using the oscilloscope.
   • Vary the distance of the movable mirror and record the corresponding time delays.
3. Calculations:
   • Use the measured time delays and the changes in the distance of the movable mirror to calculate the speed of light $c$.
4. Error Minimization:
   • Ensure precise alignment of the optical components.
   • Use high-precision timing equipment.
   • Perform measurements in a controlled environment to minimize temperature and pressure variations.

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