Two in-phase loudspeakers that emit sound with the same frequency are placed along a wall and are separated by a distance of 2.4 m. a person is standing 10.0 m away from the wall, equidistant from the loudspeakers. when the person moves 0.20 m parallel to the wall, she experiences destructive interference for the first time. what is the frequency of the sound? take the speed of sound in air to be 343 m/s.

Which of the following explains why it took so long for the public to accept the negative health effects of smoking? a)people were waiting for counter reasons, and those were presented.b)scientists had not completely finalized their results, which took 30 years.c)cigarettes were cheaply available and media channels were very inefficient.d)cigarette manufacturers were trying hard to bring an alternative into the market

Which of the following elements is in the same period as phosphorus? a. carbon c. nitrogen b. magnesium d. oxygen select the best answer from the choices provided a b c d

John throws .4 kg ball with velocity of 18 m/s. hits .2 kg bottle and bottle flies 25 m/s. how fast is ball traveling after hitting the bottle?