Answer:
wavelength = 4 m
Explanation:
For distance 6 and 8m and speed of sound in air = c.
The travel time form the various distances 6 and 8 are 6/c and 8/c respectively.
cos(wt1) + cos(wt2) = 0
for a shift in phase t1 = t - 6/c,
t2 = t - 8/c
substituting t1 and t2
cos(π - w(t - 8/c)) = cos(w(t - 6/c))
solving using trigonometry identities in radians.
we have,
π - 2πn = w(t - 8/c) - w(t - 6/c)
putting w = 2πf
π - 2πn = 2πf(t - 8/c) - 2πf(t - 6/c)
dividing both sides by π
1 - 2n = 2ft - 16(f/c) - 2ft + 12(f/c)
simplifying we have,
1 - 2n = -4(f/c)
solving for f we have,
f = c/4(2n - 1)
putting n=1 and c = 343m/s
f = (343/4)*(2(1) - 1)
f = 85.75 Hertz
wave lenght = c/f , where c= speed of sound in air , f= frequency
wave lenght = 343/85.75 = 4m
Answer:
Ultraviolet light has shorter wavelengths than infrared light. The frequency of ultraviolet light is greater than that of infrared light. Ultraviolet light is higher in energy than infrared light.
Answer: the first law of thermodynamics
Explanation:
Answer:
To obtain the power, we first need to find the work made by the force.
1) To calculate the work, we need the next equation:
So the force is given by the problem so our mission is to find 'dx' in terms of 't'
2) we know that:
So we have:
Then:
3) Finally, we replace everything:
After some calculation, we have as a result that the work is:
161.9638 J.
4) To calculate the power we need the next equation:
So
P = 161.9638/4.7 = 34.46 W
