Depends on how far away the event is and what the temperature is as this affects the speed of sound.
For example, let's say you're 600 meters away and the temperature has no affect.
The speed of sound would be roughly 340 m/s so the time it would take to hear the sound would be 600/340 = 1.76 seconds
The speed of light (c) is 3.0 X 10^8 m/s so the time it would take to see the event would be 600/3 X 10^8 = 2 X 10^-7
Subtract: 1.76 - (2 X 10^-7) = approx. 1.76
Answer:
Machine Efficiency
Explanation:
Efficiency is the percent of work put into a machine by the user (input work) that becomes work done by the machine (output work). The output work is always less than the input work because some of the input work is used to overcome friction. Therefore, efficiency is always less than 100 percent
Answer:
25032.47 W
Explanation:
Power is the time rate of doing work, hence,
P = Work done(non conservative) / time
Work done (non conservative) is given as:
W = total K. E. + total P. E.
Total K. E. = 0.5mv²- 0.5mu²
Where v (final velocity) = 7.0m/s, u (initial velocity) = 0m/s
Total P. E. = mgh(f) - mgh(i)
Where h(f) (final height) = 7.2m, h(i) (initial height) = 0 m
=> W = 0.5mv² - mgh(f)
P = [0.5mv² - mgh(f)] / t
P = [(0.5*790*7²) - (790*9.8*7.2)] / 3
P = (19355 + 55742.4) / 3 = 75097.4/3
P = 25032.47 W
Answer:
the reflected wavelength is lano = 4.55 10⁻⁷ m which corresponds to the blue color
Explanation:
This is a case of reflection interference, we must be careful
* There is a 180º phase change when light passes from the air to the soap film (n = 1,339), but there is no phase change when passing from the pomp to the plastic (n = 1.3)
* the wavelength within the film is modulated by the refractive index
λₙ = λ₀ / n
if we consider these relationships the condition for constructive interference is
2 t = (m + ½) λₙ
2t = (m + ½) λ₀ / n
λ₀ = 2t n / (m + ½)
we substitute the values
λ₀= 2 255 10⁻⁹ 1,339 / (m + ½)
λ₀ = 6.829 10⁻⁷ (m + ½)
let's calculate the wavelength for various interference orders
m = 0
λ₀ = 6.829 10⁻⁷/ ( 0 + ½ )
λ₀ = 13.6 10⁻⁷
it is not visible
m = 1
λ₀ = 6,829 10⁻⁷/ (1 + ½)
λ₀ = 4.55 10⁻⁷
color blue
m = 2
λ₀ = 6.829 10⁻⁷ / (2 + ½)
λ₀ = 2,7 10⁻⁷
it is not visible
therefore the reflected wavelength is lano = 4.55 10⁻⁷ m which corresponds to the blue color
In my opinion, the third answer makes the most sense
