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Page 200: Practice Problems
$textbf{Second hand will make 60 complete rotations}$. One each minute and there are 60 minutes in one hour.
$textbf{Minute hand will make 1 complete rotation}$ in a period of one hour,
$textbf{Hour hand will make 1/12 complete rotations }$since it will move for one out of twelve hours marked on a clock in a period of one hour, which means it will make $frac{1}{12}$ complete rotations in one hour.
$$
Delta_{theta s}=60cdot (-2cdotpi )=-377,,rm{rad}
$$
In 1 hour, the minute hand will have 1 complete rotation in the clockwise direction:
$$
Delta_{theta m}=1cdot (-2cdotpi )=-6.28,,rm{rad}
$$
In 1 hour, the hour hand will have $frac{1}{12}$ complete rotations in the clockwise direction:
$$
Delta_{theta h}=frac{1}{12} cdot (-2cdotpi )=-0.524,,rm{rad}
$$
Delta_{theta s}=-377,,rm{rad}
$$
$$
Delta_{theta m}=-6.28,,rm{rad}
$$
$$
Delta_{theta h}=-0.524,,rm{rad}
$$
In 1 hour the second hand have 60 complete rotations in the clockwise direction:
$Delta theta = (60) (-2pi) = -120 pi rad = -377 rad$
b)
In 1 hour the minute hand have 1 complete rotations in the clockwise direction:
$Delta theta = (1) (-2pi) = -2 pi rad = -6.28 rad$
c)
In 1 hour the hour hand have $dfrac{1}{12}$ of a complete rotations in the clockwise direction:
$$
Delta theta = (dfrac{1}{12}) (-2pi) = -pi/6 rad = -0.524 rad
$$
b) $-6.28 rad$
c) $-0.524 rad$
$$
a=1.85,,rm{m/s^2},
$$
and angular acceleration:
$$
alpha =5.23,,rm{rad/s^2}
$$
$$
a =alpha cdot frac{d}{2}
$$
$$
d=frac{2cdot a}{alpha}
$$
$$
d=frac{2cdot 1.85}{5.23}=0.707,,rm{m}
$$
d=0.707,,rm{m}
$$
$r = dfrac{a}{alpha} = dfrac{1.85}{5.23} = 0.3537 m$
The diameter of the wheels is:
$$
d = 2 r = 0.707 m
$$
0.707 m
$$
$$
d=0.48,,rm{m}
$$
Wheels on the truck have diameter of:
$$
d_t=0.707,,rm{m}
$$
Linear acceleration of the truck is:
$$
a_t=1.85,,rm{m/s^2}
$$
And angular acceleration of the wheels on the truck was:
$$
alpha_t=5.23,,rm{rad/s^2}
$$
$$
a=a_t=1.85,,rm{m/s^2}
$$
$$
a=alpha cdot 0.5cdot d
$$
$$
alpha =frac{a}{0.5cdot d}
$$
$$
a=a_t
$$
Inserting previous equation we get:
$$
alpha cdot 0.5cdot d=alpha_t cdot 0.5cdot d_t
$$
By solving equation we get:
$$
frac{alpha}{alpha_t}=frac{d_t}{d}
$$
Inserting value we get:
$$
frac{alpha}{alpha_t}=frac{0.707}{0.48}=1.47
$$
a=1.85,,rm{m/s^2}
$$
$$
frac{alpha}{alpha_t}=1.47
$$
$$
omega =frac{v}{0.5cdot d}
$$
And distance traveled ($s$) can be expressed through number of revolutions ($n$) as:
$$
s=ncdot dcdot pi
$$
With constant distance we get:
$$
n=frac{s}{dcdot pi}
$$