Answer:
m = 35.98 Kg ≈ 36 Kg
Explanation:
I₀ = 125 kg·m²
R₁ = 1.50 m
ωi = 0.600 rad/s
R₂ = 0.905 m
ωf = 0.800 rad/s
m = ?
We can apply The law of conservation of angular momentum as follows:
Linitial = Lfinal
⇒ Ii*ωi = If*ωf <em>(I)</em>
where
Ii = I₀ + m*R₁² = 125 + m*(1.50)² = 125 + 2.25*m
If = I₀ + m*R₂² = 125 + m*(0.905)² = 125 + 0.819025*m
Now, we using the equation <em>(I) </em>we have
(125 + 2.25*m)*0.600 = (125 + 0.819025*m)*0.800
⇒ m = 35.98 Kg ≈ 36 Kg
Answer:
1.82 rad/s².
Explanation:
Applying,
α = (ω₂-ω₁)/t..................... Equation 1
Where α = angular acceleration of the fan blades, ω₂ = final angular velocity of the fan blades, ω₁ = initial angular velocity of the fan blades, t = time.
Given: ω₂ = 350 rpm = (350×0.1047) rad/s = 36.645 rad/s. ω₁ = 250 rpm = (250×0.1047) rad/s = 26.175 rad/s, t = 5.75 s.
Substitute into equation 1
α = (36.645-26.175)/5.75
α = 10.47/5.75
α = 1.82 rad/s².
Hence the magnitude of the angular acceleration of the fan blades = 1.82 rad/s²
Does it give you options?
Answer:
c
Explanation:
efficiency is measured in % hence 0.02% is smaller than 20%