Answer:
Same frequency, shorter wavelength
Explanation:
The speed of a wave is given by
where,
f = Frequency
= Wavelength
It can be seen that the wavelength is directly proportional to the velocity.
Here the frequency of the sound does not change.
But the velocity of the sound in air is slower.
Hence, the frequency remains same and the wavelength shortens.
Answer:
λ = 162 10⁻⁷ m
Explanation:
Bohr's model for the hydrogen atom gives energy by the equation
= - k²e² / 2m (1 / n²)
Where k is the Coulomb constant, e and m the charge and mass of the electron respectively and n is an integer
The Planck equation
E = h f
The speed of light is
c = λ f
E = h c /λ
For a transition between two states we have
-
= - k²e² / 2m (1 /
² -1 /
²)
h c / λ = -k² e² / 2m (1 / ² - 1/
²)
1 / λ = (- k² e² / 2m h c) (1 / ² - 1/
²)
The Rydberg constant with a value of 1,097 107 m-1 is the result of the constant in parentheses
Let's calculate the emission of the transition
1 /λ = 1.097 10⁷ (1/10² - 1/8²)
1 / λ = 1.097 10⁷ (0.01 - 0.015625)
1 /λ = 0.006170625 10⁷
λ = 162 10⁻⁷ m
Answer: d. I or II
Explanation: A traveling wave has speed that depends on characteristics of a medium. Characteristics like linear density (μ), which is defined as mass per length.
Tension or Force () is also related to the speed of a moving wave.
The relationship between tension and linear density and speed is ginve by the formula:
So, for the traveling waves generated on a string fixed at both ends described above, ways to increase wave speed would be:
1) Increase Tension and maintaining mass and length constant;
2) Longer string will decrease linear density, which will increase wave speed, due to their inversely proportional relationship;
Then, ways to increase the wave speed is
I. Using the same string but increasing tension
II. Using a longer string with the same μ and T.
Answer:
F = 4399 KN
Explanation:
given,
mass of automobile = 890 kg
initial speed = 48 km/h
= 48 × 0.278 = 13.34 m/s
using equation of motion
v² = u² + 2 a × s
0 = 13.34² - 2 a ×0.018
a = 4943.21 m/s²
F = m × a
F = 890 × 4943.21
F = 4399456.9 N
F = 4399 KN
hence, the Net force is F = 4399 KN