v = speed of the source of sound or the train towards the listener or switchman = 40 m/s
V = actual speed of sound = 340 m/s
f = actual frequency of sound as emitted from source or the train = 1000 Hz
f' = frequency as observed by the listener or by switchman = ?
Using Doppler's law , frequency observed by a listener from a source moving towards it is given as
f' = V f /(V - v)
inserting the values
f' = 340 x 1000 /(340 - 40)
f' = 340 x 1000/300
I believe if the objects speed increases!
i-beams are the choice for structural skyscrapers because of their high functionality.
the shape of i-beams makes them excellent for unidirectional bending parallel to the web.
the horizontal flanges resist the bending movement, while the web resists the shear stress.
♡ hope this helped! ♡
Answer:
The minimum thickness of the Lucite plate is 0.670 μm.
Explanation:
Given that,
Wavelength = 650.0 nm
Index of refraction = 1.485
We need to calculate the minimum thickness of the Lucite plate
Using formula of thickness
Where, n = Index of refraction
= wavelength
Put the value into the formula
Hence, The minimum thickness of the Lucite plate is 0.670 μm.