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8090 [49]
3 years ago
5

The room contains a refrigerator, operated by an electric motor. The motor does work at the rate of 438 W when it is running. Th

e refrigerator removes heat from the food storage space at a rate of 450 W when the motor is running. In an effort to cool the room, you open the refrigerator door and let the motor run continuously. At what net rate is heat added to (+) or subtracted from (−) the room and all of its contents?
Physics
1 answer:
yKpoI14uk [10]3 years ago
8 0

Answer: Heat is removed from the room at 12W

Explanation:

Energy (heat) is generated by the the rotor at a rate

∆Q/t = 438W

Work is done (heat removal) by the refrigerator at a rate

∆W/t = 450W

Net rate of heat removed =

∆Q/t - ∆W/t

= (438 - 450)W

= -12W

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a star that suddenly increases greatly in brightness because of a catastrophic explosion that ejects most of its mass.
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HEYYYY!! PLEASE HELP!!! Describe three machines that humans have designed and explain how the mechanical advantage is used.!!
satela [25.4K]

Answer:

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5 0
2 years ago
A spinning disc rotating at 130 rev/min slows and stops 31 s later. how many revolutions did the disc make during this time?
gayaneshka [121]
F = 130 revs/min = 130/60 revs/s = 13/6 revs/s
t = 31s
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wf = 0 rads/s = wi + at
a = -wi/t = -13π/3 × 1/31 = -13π/93 rads/s²
wf² - wi² = 2a∅
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3 0
2 years ago
A 500-g lump of clay is dropped onto a 1-kg cart moving at 60 cm/s. The clay is moving downward at 30 cm/s just before l dith t
viktelen [127]

Answer:

The speed of the cart and clay after the collision is 50 cm/s .

Explanation:

Given :

Mass of lump , m = 500 g = 0.5 kg .

Velocity of lump , v = 30 cm/s .

Mass of cart , M = 1 kg .

Velocity of cart , V = 60 cm/s .

We know by conservation of momentum :

mv+MV=(m+M)v'

Here , v' is the speed of the cart and clay after the collision .

Putting all value in above equation .

We get :

0.5\times 30+1\times 60=(0.5+1)\times v'\\\\v'=\dfrac{15+60}{1.5}\\\\v'=50\ cm/s

Hence , this is the required solution .

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The primary reason a light bulb emits light is due to
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3 years ago
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