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Alenkasestr [34]
3 years ago
10

The tub of a washer goes into its spin-dry cycle, starting from rest and reaching an angular speed of 6.0 rev/s in 11.0 s. At th

is point, the person doing the laundry opens the lid, and a safety switch turns off the washer. The tub slows to rest in 14.0 s. Through how many revolutions does the tub turn during this 25 s interval? Assume constant angular acceleration while it is starting and stopping.
Physics
1 answer:
sleet_krkn [62]3 years ago
3 0

Answer

given,

ω₁ = 0 rev/s

ω₂ = 6 rev/s

t = 11 s

Using equation of rotational motion

The angular acceleration is

  ωf - ωi = α t

  11 α = 6 - 0

      = 0.545 rev/s²

The angular displacement

  θ₁= ωi t + (1/2) α t²

  θ₁= 0 + (1/2) (0.545)(11)^2

  θ₁= 33 rev

case 2

ω₁ = 6 rev/s

ω₂ = 0 rev/s

t = 14 s

Using equation of rotational motion

The angular acceleration is

  ωf - ωi = α t

  14 α = 0 - 6

        = - 0.428 rev/s²

The angular displacement

  θ₂= ωi t + (1/2) α t²

  θ₂= 6 x 14 + (1/2) (-0.428)(14)^2

  θ₂= 42 rev

total revolution in 25 s is equal to

θ =  θ₁ +  θ₂

θ =  33 + 42

θ = 75 rev

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Complete Question

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Answer:

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Explanation:

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   Now referring to the formula above

i.e          Kinetic energy of 9 kg  block = initial energy stored - energy lost as a result of friction

                \frac{1}{2} mv^2 = 112.86 - \mu_kmgx

                v^2 = \frac{2(112.86 -\mu_kmgx)}{m}

                v = \sqrt{\frac{2(112,86- \mu_kmgx)}{m}}

and we are told that coefficient of friction  = 0.4 and the mass is 9 kg ,the acceleration due to gravity = 9.8m/s^2  this displacement length of spring = 0.6

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what is the acceleration of a 2,000- kilogram truck if a force of 4,200. N is used to make it start moving forward?
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Newton's 2nd law of motion:              Force = (mass) x (acceleration)

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algol13

Answer:

D. Friction and air resistance created heat on his trip up the hill.

Explanation:

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Most of the energy transformation is not purely 100%.

When energy is transformed, some are usually wasted.

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