Answer:
a)106.48 x 10⁵ kg.m²
b)144.97 x 10⁵ kgm² s⁻¹
Explanation:
a)Given
m = 5500 kg
l = 44 m
The moment of inertia for one blade
= 1/3 x m l²
where m denotes the mass of the blade
l represents the length of each blade.
Substituting the necessary values, the moment of inertia for one blade is
= 1/3 x 5500 x 44²
= 35.49 x 10⁵ kg.m²
Total moment of inertia for 3 blades
= 3 x 35.49 x 10⁵ kg.m²
= 106.48 x 10⁵ kg.m²
b) The angular momentum 'L' is calculated using
L = x ω
where,
= the moment of inertia of the turbine i.e 106.48 x 10⁵ kg.m²
ω= angular velocity =2π f
f represents the frequency of rotation of the blade i.e 13 rpm
f = 13 rpm=>= 13 / 60 revolutions per second
ω = 2π f => 2π x 13 / 60 rad / s
L= x ω =>106.48 x 10⁵ x 2π x 13 / 60
= 144.97 x 10⁵ kgm² s⁻¹