1
a) 1.8/1.2
b) (1.8/1.2)*(180/p)
c) 0.620*2.4
5
Q(t) = 4t-3t2+t3
a) w(t) = dQ/dt
= 4 - 6t +3t2 w(2)
w(4)
b) [w(4) - w(2)
]/2
c) a(t) = dw/dt
= -6 + 6t
a(2) a(4)
9
h = 1/2 gt2 so t = sqrt(2h/g)
(Qfinal - 0) /t = 2.5*2p/t
11
a) a = [wfinal
- winitial]/t
assuming constant acceleration and w
= 2p*rev/min*60
b) Q = winitial*t
+ 1/2 at2 and divide
by 2p to have revolutions
33
a) w = v/r
b) ar = v2/r
c) 0 (zero)
35
a) a = [wfinal
- winitial]/t
= (0 - 150)/(2.2*60)
b) Q = winitial*t
+ 1/2 at2 = 150*2.2*60 - 1/2 a
(2.2*60)2
where a from a)
c) acceleration is constant so it is the same at any moment
between 0 and 2.2 hours.
linear acceleration a = a*r
where a is from a) and r = 0.5 m
d) net acceleration is the vector sum of tangential and
radial acceleration (they are always at right angle)
the magnitude of the sum is
sqrt(ar2 + at2) where
at is from c) and ar = 752/0.5
39
a) linear velocity = v = at = 0.5*15
so radial acceleration ar = v2/r
and magnitude of the net acceleration is sqrt(ar2
+ at2) where at = 0.5
b) angle can be calculated from Q
= tan-1 (ar /at)