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Rasek [7]
2 years ago
5

A ceiling fan is turned on and reaches an angular speed of 132 rev/min in 20 s. It is then turned off and coasts to a stop in an

additional 40 s. The ratio of the average angular acceleration for the first 20 s to that for the last 40 s is which of the following?
a. 2
b. -0.5
c. 0.5
d. -2
Physics
1 answer:
Mkey [24]2 years ago
8 0

Answer:

Explanation:

α = (ωf - ωi)/t

acceleration phase

ωf = 132 rev/min (2π rad/rev / 60 s/min) = 4.4π rad/s

α₁ = (4.4π - 0)/20 = 0.22π rad/s²

α₂ = (0 - 4.4π)/40 = - 0.11π rad/s²

α₁/α₂ = 0.22π/- 0.11π = -2

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Answer:

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Given :

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In coordinate system ,

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E=-\dfrac{2xyz^2}{\delta x }-\dfrac{2xyz^2}{\delta y }-\dfrac{2xyz^2}{\delta z }\\\\E=-2yz^2-2xz^2-4xyz

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Explanation:

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3 years ago
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HELP!!
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When light travels from a medium it moves faster in (such as air) to a medium it moves slower in (such as glass) its velocity de
shutvik [7]

Answer:

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A neutral solid metal sphere of radius 0.1 m is at the origin, polarized by a point charge of 2 × 10−8 C at location m. At locat
liraira [26]

Answer: E = 1.8 *10 ^{4} N

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