The formula if he copies correctly if not plain numbers
The first thing we are going to do is find the equation of motion:
ωf = ωi + αt
θ = ωi*t + 1/2αt^2
Where:
ωf = final angular velocity
ωi = initial angular velocity
α = Angular acceleration
θ = Revolutions.
t = time.
We have then:
ωf = (7200) * ((2 * pi) / 60) = 753.60 rad / s
ωi = 0
α = 190 rad / s2
Clearing t:
753.60 = 0 + 190*t
t = 753.60 / 190
t = 3.97 s
Then, replacing the time:
θ1 = 0 + (1/2) * (190) * (3.97) ^ 2
θ1 = 1494.51 rad
For (10-3.97) s:
θ2 = ωf * t
θ2 = (753.60 rad / s) * (10-3.97) s
θ2 = 4544,208 rad
Number of final revolutions:
θ1 + θ2 = (1494.51 rad + 4544.208 rad) * (180 / π)
θ1 + θ2 = 961.57 rev
Answer:
the disk has made 961.57 rev 10.0 s after it starts up
According to my opinion,
NO, I'd not feel comfortable.
Substitution ciphers in the world of encryption can be
cracked very easily. By looking for patterns like one letter words, double
letter patterns, and knowing rules such as all words must contain at least an
a, e, i, o, u or y, you are probably able to decipher this with so much ease. While
this information and the frequency of letters used in the encrypted message might
be helpful, it might not be a perfect process.
Graphical user interface.
Hope I helped :)