7.The wavelength λ of the microwaves can be measured with the Michelson interferometer shown below. (An interferometer is a device that can be used to measure lengths or changes in length with great accuracy by means of interference effects.)
The transmitter and receiver horns should each be approximately 10 cm from the center of the track. Place the two full (aluminum) reflectors at right angles to each other (as measured by the protractor) and at distances d 1 and d 2 from the center of the track. Place the half (lucite) reflector at an angle of 45° with respect to the incident beam. Adjust d 1 (the position of the full reflector opposite the receiver) until the receiver reading is a minimum. Next, adjust d 1 (the position of the full reflector opposite the transmitter) until the receiver reading is a minimum. Then vary d 1 between 15 cm and 40 cm, and record at least 15 values of d 1 for which the receiver output is a minimum. Knowing that the distance between adjacent minima is λ/2 , calculate λ for each pair of adjacent minima, and determine the average wavelength. Compare this value with the wavelength recorded in step 1.