A physics student with too much free time drops a watermelon from the roof of a building. He hears the sound of the watermelon going "splat" after a time interval of 2.42 s.
You may ignore air resistance. How high is the building? The speed of sound is 340 m/s .
Take the free fall acceleration to be g = 9.80 m/s^2.
2007-01-28 18:46:57 · 5 answers · asked by erica s 1 in Science & Mathematics ➔ Physics
The time from drop to hearing the sound has two components: The fall time of the watermelon = √2gh, and the time it took for the sound to reach him = h/vs. Therefore the total time is
2.42 = √[2*h/g] + h/340
2.42 - h/340 = √2*h/g
2.42^2 - 2*2.42/340*h + h^2/340^2 = .204*h
h^2/115600 - .22*h + 5.856 = 0
Solve the quadratic equation
2007-01-28 19:41:44 · answer #1 · answered by gp4rts 7 · 1⤊ 0⤋
indexed right here are the equations: a = consistent = -9.8 m/s² (in any respect cases) V = Vo + a*t Y = Yo + Vo*t + ½*a*t² (said as 'position' interior the question) Vo is +9.8 m/s and Yo is 0 on the right of the progression. positioned the time values into the above equations and fill interior the chart. The solutions to both ?s less than it is going to grow to be obvious. the right of the flight is even as V = 0 and the roof factor implies Y = 0
2016-10-16 06:06:09 · answer #2 · answered by ? 4 · 0⤊ 0⤋
He can count the floors of the building.
1 floor is about 3meters.
2007-01-28 18:57:04 · answer #3 · answered by mageros 3 · 0⤊ 0⤋
wild stab...3 stories
2007-01-28 18:55:26 · answer #4 · answered by ___ 5 · 0⤊ 0⤋
26.85 meters
2007-01-28 19:42:25 · answer #5 · answered by Jestnii 2 · 0⤊ 0⤋