Answer:
2.81 kW
Explanation:
Initial power output, P = 20.0 kW
Initial amplitude, A = 1.20 m
Final Amplitude, A = 0.450 m
Power is proportional to extracted energy which is proportional to the intensity of the wave and intensity of the wave is directly proportional to the square of the amplitude.
P ∝ E ∝ I ∝ A²
Substitute the values to find the value of power produced:
Answer:
The moment of inertia of the turntable about the rotation axis is 0.0225 kg.m²
Explanation:
Given;
radius of the turnable, r = 60 cm = 0.6 m
rotational kinetic energy, E = 0.25 J
angular speed of the turnable, ω = 45 rpm
The rotational kinetic energy is given as;
where;
I is the moment of inertia about the axis of rotation
ω is the angular speed in rad/s
Therefore, the moment of inertia of the turntable about the rotation axis is 0.0225 kg.m²
Answer:
The current in the motor in this case is 13.2 A
Explanation:
Given:
Resistance 5 Ω
Emf V
Induced emf V
When motor run at half speed due to load increased then induced emf is also reduced to half of its value
So new induced emf in our case is given by,
V
Where
A
Therefore, the current in the motor in this case is 13.2 A