Answer:
The smallest separation distance between the speakers is 0.71 m.
Explanation:
Given that,
Two speakers, one directly behind the other, are each generating a 240-Hz sound wave, f = 240 Hz
Let the speed of sound is 343 m/s in air. The speed of sound is given by the formula as :
![v=f\lambda\\\\\lambda=\dfrac{v}{f}\\\\\lambda=\dfrac{343\ m/s}{240\ Hz}\\\\\lambda=1.42\ m](https://tex.z-dn.net/?f=v%3Df%5Clambda%5C%5C%5C%5C%5Clambda%3D%5Cdfrac%7Bv%7D%7Bf%7D%5C%5C%5C%5C%5Clambda%3D%5Cdfrac%7B343%5C%20m%2Fs%7D%7B240%5C%20Hz%7D%5C%5C%5C%5C%5Clambda%3D1.42%5C%20m)
To produce destructive interference at a listener standing in front of them,
![d=\dfrac{\lambda}{2}\\\\d=\dfrac{1.42}{2}\\\\d=0.71\ m](https://tex.z-dn.net/?f=d%3D%5Cdfrac%7B%5Clambda%7D%7B2%7D%5C%5C%5C%5Cd%3D%5Cdfrac%7B1.42%7D%7B2%7D%5C%5C%5C%5Cd%3D0.71%5C%20m)
So, the smallest separation distance between the speakers is 0.71 m. Hence, this is the required solution.
Answer:
471392.4 N
Explanation:
From the question,
Just before contact with the beam,
mgh = Fd.................... Equation 1
Where m = mass of the beam, g = acceleration due to gravity, h = height. F = average Force on the beam, d = distance.
make f the subject of the equation
F = mgh/d................ Equation 2
Given: m = 1900 kg, h = 4 m, d = 15.8 = 0.158 m
Constant: g = 9.8 m/s²
Substitute into equation 2
F = 1900(4)(9.8)/0.158
F = 471392.4 N
B. A pot of boiling water represents a system that is completely open.
Answer:
c. 12,500
Explanation:
Original number of atoms = 100,000 atoms
Half- life = 10min
Unknown:
The number of atoms that will remain after 10min = ?
Solution:
The half - life is the time taken for half of a radioactive substance to decay by half.
Time taken Number of atom half life
10min 100000 _
20min 50000 1
30min 25000 2
40min 12500 3