A radio telescope consists of two antennae separated by a distance of 235 m. Both antennae are tuned to 26 MHz. The signals from the two antennae are fed into a common amplifier, but one signal is passed through a phase adjuster that delays the phase by a chosen amount, 6, so that the telescope effectively "looks" in different directions. When 8=0, plane radio waves that are incident vertically on the antennae produce signals that add constructively at the amplifier. What is the minimum phase delay that should be introduced in order that signals coming from an angle 0 = 18 degrees from the vertical will add constructively at the amplifier? Give your answer as a positive number in radians, and use 3 x 108 m/s for the speed of light. Number

A radio telescope consists of two antennae separated by a distance of 235 m. Both antennae are tuned to 26 MHz. The signals from the two antennae are fed into a common amplifier, but one signal is passed through a phase adjuster that delays the phase by a chosen amount, 6, so that the telescope effectively "looks" in different directions. When 8=0, plane radio waves that are incident vertically on the antennae produce signals that add constructively at the amplifier. What is the minimum phase delay that should be introduced in order that signals coming from an angle 0 = 18 degrees from the vertical will add constructively at the amplifier? Give your answer as a positive number in radians, and use 3 x 108 m/s for the speed of light. Number