Answer:
8
Explanation:
Applying,
v = λf................ Equation 1
Where v = velocity/ speed of the wave, λ = wave length of the wave, f = number of waves the person surf in one seconds.
make f the subject of the equation
f = v/λ............ Equation 2
From the question,
Given: v = 1.6 m/s, λ = 24 m
Substitute these values into equation 2
f = 1.6/24
f = 0.0667 wave/seconds.
If,
in one seconds, the person surf a total wave crest of 0.0667
Therefore,
in one hours, he will surf a total wave crest of (0.0667×60×60) = 240 waves crest
He rides for every 30th wave crest,
Hence,
number of wave crest the person surf in one hour = 240/30 = 8
When water vaporizes into the air, it becomes humid out.
Answer:
Energy needed = 54.02 J
Explanation:
the Energy in an elastic spring from hookes law is given as
F= ke , therefore the energy (E) is
E = 
K = 19.5 N/cm
e = 1.39cm
E =
x 19.5 x 1.39
E = 13.55 J
The energy to stretch the spring for 6.93cm is
E =
x 19.5 x 6.93
E = 67.57 J
The more energy needed for the further stretch is
67.57 - 13.55
Energy needed = 54.02 J