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Klio2033 [76]
3 years ago
6

A grindstone of radius 4.0 m is initially spinning with an angular speed of 8.0 rad/s. The angular speed is then increased to 12

rad/s over the next 4.0 seconds. Assume that the angular acceleration is constant. Through how many revolutions does the grindstone turn during the 4.0-second interval?
Physics
1 answer:
PSYCHO15rus [73]3 years ago
6 0

Answer: 6.36

Explanation:

Given

Radius of grindstone, r = 4 m

Initial angular speed of grindstone, w(i) = 8 rad/s

Final angular speed of the grindstone, w(f) = 12 rad/s

Time used, t = 4 s

Angular acceleration of the grinder,

α = Δw / t

α = w(f) - w(i) / t

α = (12 - 8) / 4

α = 4/4 = 1 rad/s²

Number of complete revolution in 4s =

Δθ = w(i).t + 1/2.α.t²

Δθ = 8 * 4 + 1/2 * 1 * 4²

Δθ = 32 + 1/2 * 16

Δθ = 32 + 8

Δθ = 40 rad/s

40 rad/s = 40/2π rpm = 6.36 rpm

Therefore, the grindstone does 6.36 revolutions during the 4 s interval

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Answer:

Explanation:

Time to cover first 100 km = 1 hour.

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Time to cover next 42 km = 1 hour .

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Distance to be covered = 310 - 142

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3 years ago
Pascal's Principle states that (a) If we apply pressure to a fluid in a sealed container, the pressure will be felt undiminished
nika2105 [10]

Answer:

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Explanation:

Pascal´s Principle can be applied in the hydraulic press:

If we apply a small force (F1) on a small area piston A1, then, a pressure (P) is generated that is transmitted equally to all the particles of the liquid until it reaches a larger area piston and therefore a force (F2) can be exerted that is proportional to the area(A2) of the piston.

P=F/A

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F1/ A1= F2/ A2

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-Dominant- [34]

Explanation:

LD₁ = 10⁵ mm⁻²

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PLLLLLLZ HELP 15 POINTS
amid [387]
<h2>Option A is the correct answer.</h2>

Explanation:

A 10-ω resistor and a 30-ω resistor are connected in series across a 100-V battery

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We have

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