False ...................
Answer:
except ii and iii
Explanation:
The angle of reflection is the angle to the normal the white rays strikes the water surface and it is the incidence angle. Since the white light is moving from less dense medium to a denser medium or a medium with a higher refractive index; the angle of refraction will be less than 30 degrees. Total internal reflection cannot occur because the white light is traveling from a less dense medium to a denser medium.
Answer:
1) λ = 24.7 cm, 2) f = 13.88 Hz, 3) L = 117.3 cm
Explanation:
1) This is a resonance process, that is, the wave going downwards will interfere with the wave going upwards.
This is a tube with one end closed and the other open, at the closed end there is a node and at the open end a belly, so the resonances are
L = λ / 4
λ = 4L 1st harmonic
λ = 4L / 3 third harmonic
λ = 4L / 5 fifth harmonic
λ = 4L / n ’ n’ odd number n ’= (2n +1)
the wavelength is requested for the eighth resonance n = 8, the corresponding prime number is
n ’= 2 8 +1
n ’= 17
we substitute
λ = 4 105/17
λ = 24.7 cm
2) the speed of the wave is related to the wavelength and frequency
v = λf
f = v /λ
f = 343 / 24.7
f = 13.88 Hz
3) the next resonance occurs for n = 9, so the prime number is
n ’= 2 9 +1
n ’= 19
L = n’ λ / 4
L = 19 λ / 4
We must suppose a value for the wavelength, if the wavelength is present in the tube and the length of the column increases, the resonance number increases
L = 19 24.7/4
L = 117.3 cm
