mechanical questions
in
turbofan engine, the thrust is only generated by the fan, and work
generated by the turbine core is only developed to move the fan and
compressor of the entire turbine
true or false
the
air fuel ratio used in jet engine is very small
true or false
the
definition of thermodynamics is the study of the behavior of gases
and heat
true or false
An aircraft is in level flight at airspeed v(t) m/s with thrust
T(t) N at cruising altitude. Suppose that at v0 = 250 m/s, the
aerodynamic drag experienced by the aircraft at this altitude
is:
Fd(v) = 0.25v 2 . (1)
Then, an extremely simplified model relating v(t) to T(t)
is:
mv˙(t) + Fd(v(t)) = T(t), (2)
where m = 25000 kg. Assume v(t) is always positive.
Question 1. Linearize (2) at v0 = 250 m/s, and an appropriate
nominal...
I went to the 99 Cent store the other day and got really excited
at some amazing bargains: The scented candles that normally sold
for $5.99 at Target was at the 99 Cent Store. After grabbing about
a dozen of them and stuffing them into my shopping basket, I
realized they weren’t 99 cents! They were marked as $1.99. I was a
little annoyed and not a little disappointed as I mumbled to
myself, “the audacity of them to keep...
I went to the 99 Cent store the other day and got really excited
at some amazing bargains: The scented candles that normally sold
for $5.99 at Target was at the 99 Cent Store. After grabbing about
a dozen of them and stuffing them into my shopping basket, I
realized they weren’t 99 cents! They were marked as $1.99. I was a
little annoyed and not a little disappointed as I mumbled to
myself, “the audacity of them to keep...
(a) Prove that Sn is generated by the elements in the set {(i
i+1) : 1≤i≤n}.
[Hint: Consider conjugates, for example (2 3) (1 2) (2
3)−1.]
(b) ProvethatSn isgeneratedbythetwoelements(12)and(123...n) for
n ≥ 3.
(c) Prove that H = 〈(1 3), (1 2 3 4)〉 is a proper subgroup of
S4.
I stepped on a track and lifted my foot explain how that
sensation got to my brain. Where I became aware of it and why my
foot lifted before I was aware