The diagram below shows an arrangement used to investigate double slit interference using microwaves.
The diagram below shows the view from above:
The microwaves from the transmitter are polarised. These waves are detected by the aerial in the microwave detector (probe). The aerial is a vertical metal rod.
The detector is moved along the dotted line UY. As it is moved, maximum and minimum signals are detected. Maximum signals are first detected at points V and W. The next maximum signal is detected at the position X.
The distances between each of the two slits, S1 and S2 and the microwave receiver when the aerial is in position X are S1X = 0.3335 m and S2X = 0.3615 m
Select the three correct reasons that explain why the signal strength falls to a minimum between U and V, and between V and W.
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Reason 1
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Reason 2
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Reason 3
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A
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Waves are out of phase
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Gives rise to a path difference
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Constructive interference occurs
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B
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Waves are out of phase
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Gives rise to a path difference
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Destructive interference occurs
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C
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Path difference for the two waves
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Gives rise to a phase difference
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Destructive interference occurs
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D
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Path difference for the two waves
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Gives rise to a phase difference
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Constructive interference occurs
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