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3 years ago

The universe is sometimes described as an isolated system. Why?

1 answer:

8 0

Answer and Explanation :The universe means it includes everything, even the things which we can not see is an isolated system because universe has no surroundings. an isolated system does not exchange energy or matter with its surroundings.Sometime universe is treated as isolated system because it obtains lots of energy from the sun but the exchange of matter or energy with outside is almost zero.

the total energy of an isolated system is always constant means total energy of universe is also constant
there is no exchange of matter or energy in an isolated system

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3 years ago

The amplitudes of the displacement and acceleration of an unbalanced motor were measured to be 0.15 mm and 0.6*g, respectively.

ehidna [41]

Answer:

The speed of shaft is 1891.62 RPM.

Explanation:

given that

Amplitude A= 0.15 mm

Acceleration = 0.6 g

we can say that acceleration= 0.6 x 9.81

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We know that

$a=\omega ^2A$

So now by putting the values

$a=\omega ^2A$

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We know that

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198.0=2πN/60

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So the speed of shaft is 1891.62 RPM.

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3 years ago

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Answer:

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Explanation:

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Lilac~

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2 years ago

D. projectile

Colt1911 [192]

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Explanation:

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3 years ago

For a bronze alloy, the stress at which plastic deformation begins is 275 MPa, and the modulus of elasticity is 115 GPa. (a) Wha

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Answer:

89375 N

Explanation:

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