You and a friend are sitting in the bleachers of a major league baseball park, 131 m from home plate on a day when the temperature is 20° C. Your friend is listening to the radio commentary with headphones while watching. The broadcast network has a microphone located 17 m from home plate to pick up the sound as the bat hits the ball. This sound is transferred as an EM wave a distance of 74,000 km by satellite from the ball park to the radio.
(a) What is the shortest time interval between the bat hitting the ball and one of you hearing the sound?
(b) How much later does the other person hear the sound?
The answers are (a) 0.296 s and (b)
0.0857 s
Please show all work. Thank you in advance. :)
(a) What is the shortest time interval between the bat hitting the ball and one of you hearing the sound?
(b) How much later does the other person hear the sound?
The answers are (a) 0.296 s and (b)
0.0857 s
Please show all work. Thank you in advance. :)
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the person without the headphones will hear the sound in a time of
time = distance/speed of sound = 131m/343m/s = 0.382 s
the sound heard by the person listening to radio will travel as a sound wave 17m to the microphone, then make a round trip of 74,000 km as a radio wave traveling at the speed of light
the time for this trip is
time = 17m/343m/s + 74,000km/300,000km/s = 0.0496s+0.247s = 0.296s
time = distance/speed of sound = 131m/343m/s = 0.382 s
the sound heard by the person listening to radio will travel as a sound wave 17m to the microphone, then make a round trip of 74,000 km as a radio wave traveling at the speed of light
the time for this trip is
time = 17m/343m/s + 74,000km/300,000km/s = 0.0496s+0.247s = 0.296s