Answer:
22425 J
Explanation:
From the question,
Applying
Q = cm(t₂-t₁).................. Equation 1
Where Q = Thermal Energy, c = specific heat capacity of aluminium, m = mass of aluminium, t₂ = Final Temperature, t₁ = Initial Temperature.
Given: c = 897 J/kg.K, m = 1.0 kg, t₁ = 50 °C, t₂ = 25 °C (The final temperature is reduced by half)
Substitute these values into equation 1
Q = 897×1×(25-50)
Q = 897×(-25)
Q = -22425 J
Hence the thermal energy lost by the aluminium is 22425 J
Answer:
Explanation:
This question is based on the Law of Conservation of Angular Momentum.
Angular momentum (L) equals the moment of inertia (I) times the angular speed (ω).
L = Iω
If momentum is conserved,
I₁ω₁ = I₂ω₂
Data:
I₁ = 3.5 kg·m²s⁻¹
ω₁ = 6.0 rev·s⁻¹
I₂ = 0.70 kg·m²s⁻¹
Calculation:

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