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4 years ago

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A centrifuge in a biology laboratory rotates at an angular speed of 3,400 rev/min. When switched off, it rotates 48.0 times befo

re coming to rest. Find the constant angular acceleration of the centrifuge (in rad/s2). Consider the direction of the initial angular velocity to be the positive direction, and include the appropriate sign in your result.

1 answer:

IgorLugansk [536]4 years ago

7 0

Answer:

- 210 rad/s²

Explanation:

n = frequency of rotation = 3400/60 = 170/3 per sec.

angular velocity ω ( 0 ) at time 0 = 2π n = 2π x 170/3

angular velocity at time t = ω(t) = 0

now, ω²( t) = w²(o) + 2α Φ ( α = angular acceleration and Φ = angular displacement) = 2π x 48 rad.

0 = ( 2π x 170/3 )² + 2α x 48 x 2π

α = - (2π x 170 x 170 )/ (3 x 3 x 2 x 48 ) = 210 rad / s²

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Answer:

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18² = 12² + 2*3*S

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