Answer:
27.6 m/s
5.64 s
Explanation:
Given:
Δy = 39 m
a = -9.8 m/s²
v = 0 m/s
Find: v₀
v² = v₀² + 2aΔy
(0 m/s)² = v₀² + 2 (-9.8 m/s²) (39 m)
v₀ = 27.6 m/s
Find: 2t
Δy = vt − ½ at²
(39 m) = (0 m/s) t − ½ (-9.8 m/s²) t²
t = 2.82 s
2t = 5.64 s
5 sets
Explanation:
Matches are played best of five sets. The first four sets are played to 25 points, with the final set being played to 15 points. A team must win a set by two points. There is no ceiling, so a set continues until one of the teams gains a two-point advantage. Previously, all sets were to 15 points, with the first four sets having a ceiling of 17 and the final set requiring at least a two-point winning advantage.
The moon is closer to the earth and the pull of gravity is reliant on distance.
<u>(A). The wavelength decreases by a factor of 3</u>.
<h3>Introduction :</h3>
Hi ! We all know that all type of electromagnetic wave, will have the same velocity as the speed of light, because light is part of electromagnetic wave too. The value of it is 300,000 km/s or m/s. As a result of this constant property, <u>the shorter the wavelength, the greater the value of the electromagnetic wave frequency</u>. This relationship can also be expressed in this equation:
With the following condition :
- c = the constant of the speed of light in a vacuum ≈ m/s
- = wavelength (m)
- f = electromagnetic wave frequency (Hz)
<h3>Explanation</h3>
In this problem, we underline one concept, namely : "<u>the shorter the wavelength, the greater the value of the electromagnetic wave frequency</u>". In question, the frequency of the waveform will increase by a factor of 3 from the beginning. So, to keep this value constant, the wavelength should be reduced by a factor of 3 from the initial condition.
<h3>Proof</h3>
Assume that:
- c = c' = speed of the electromagnetic wave is always the same (constant).
- = initial wavelength =
- f = initial frequency = f
- f' = final frequency = 3f
Let we count :
- = final wavelength = ...
Step by step :
(Q.E.D)
<h3>Conclusion</h3>
So, if the frequency value is increased by a factor of 3 from its original, then the wavelength will decrease by a factor of 3 from the original.
<h3>See More</h3>