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Iteru [2.4K]
3 years ago
10

A wind turbine is initially spinning at a constant angular speed. As the wind's strength gradually increases, the turbine experi

ences a constant angular acceleration 0.155 rad/s2. After making 2870 revolutions, its angular speed is 127 rad/s. (a) What is the initial angular velocity of the turbine? (b) How much time elapses while the turbine is speeding up?
Physics
1 answer:
Brums [2.3K]3 years ago
4 0

Answer:

a) Initial angular velocity of the turbine = 102.66 rad/s

b) Time elapsed while the turbine is speeding up = 157 s

Explanation:

a) Considering angular motion of turbine:-

Initial angular velocity, u =  ?

Acceleration , a = 0.155 rad/s²

Final angular velocity, v  = 127 rad/s  

Angular displacement, s = 2π x 2870 = 18032.74 rad

We have equation of motion v² = u² + 2as

Substituting

   v² = u² + 2as

    127² = u² + 2 x 0.155 x 18032.74

    u = 102.66 rad/s

Initial angular velocity of the turbine = 102.66 rad/s

b) We have equation of motion v = u + at

Initial angular velocity, u =  102.66 rad/s

Acceleration , a = 0.155 rad/s²

Final angular velocity, v  = 127 rad/s  

Substituting

  v = u + at

  127  = 102.66 + 0.155 x t = 157 s

Time elapsed while the turbine is speeding up = 157 s

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Answer:

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Number of breakdown = 1 at 20 hour and another at 140 hour = 2

so it will be  = (Total up time) ÷ (number of breakdowns)      .......2

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and

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Answer:

<u>Part A:</u>

Unknown variables:

velocity of the astronaut after throwing the tank.

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To obtain the velocity of the astronaut we use this equation:

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Hi there!

Due to conservation of momentum, the momentum of the oxygen tank when it is thrown away must be equal to the momentum of the astronaut but in opposite direction. In other words, the momentum of the system astronaut-oxygen tank is the same before and after throwing the tank.

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