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Many people believe that a vacuum created inside a

pashok25 [27]

Answer:Due to the pressure difference created by rotating fans.

Explanation:

In most of the vacuum cleaners, there is an area which is of disc shape and it is in right next to the motor. There are several fans within the disc that spin at a very high velocity.

The blades will push the air outside of the disk.There is no air in inside of the disc and air pressure creates which pushes air inside the disk to replace the missing air.

So motor is pushing the air outside and to maintain this pressure the air is pushing toward inside with dirt.

3 0

3 years ago

Why do plants not need digistive system

WINSTONCH [101]

Humans need a digestive system to do cellular respiration, which produces energy used for growth and movement.

Plants do not need one as they make their own energy through photosynthesis. The process produces glucose, which is a form of energy for the plants.

4 0

3 years ago

Read 2 more answers

Why is aluminum suitable material to use in makinv cans based on its physical and chemical properties

Llana [10]

low density, malleable, easy to form into shapes, not very chem reactive

7 0

3 years ago

12. An astronaut whose mass is 70 kg on Earth's surface 12 poi

Vadim26 [7]

Her mass is still 70 kg

Explanation:

The mass of an object is an intrinsec property of the object that gives a measure of the "amount of matter" inside the object.

Being an intrinsec property, it depends only on the object itself, not on its location: therefore, the mass of an object is always the same in different locations. Therefore, the mass of the astronaut in the spacecraft is still the same as if she was on the earth, 70 kg.

On the contrary, the weight of an object is the force of gravity acting on the object, and it is given by

$F=mg$

where

m is the mass

g is the acceleration of gravity

While m is always the same, the value of g changes based on the location: therefore, the weight of an object changes depending on the location.

Learn more about gravity:

brainly.com/question/1724648

brainly.com/question/12785992

#LearnwithBrainly

3 0

3 years ago

Air is compressed from 14.7 psia and 60°F to a pressure of 150 psia while being cooled at a rate of 10 Btu/lbm by circulating wa

iren2701 [21]

Answer:

A. 6.36 lbm/s

b. $T_2=341\textdegree F$

Explanation:

a. Given the following information;

#Compressor inlet:

Air pressure, $P_1=14.7psia,T_1=60\textdegree F$

#Compressor outlet:

$Air \ Pressure, P_2=150psia\\\\Air \ volume \ flow \ rate, \dot V_1=5000ft^3/min$

#Cooling rate,

$q_{out}=10Btu/lbm, \dot W=700hp$

# From table A-1E

Gas constant of air $R=0.3704\ psia.ft^3/lbm.R$

Specific enthalpy at $P_1=520R-h_1=124.27Btu/lbm$

Using the mass balance:

$\dot m_{in}-\dot m_{out}=\bigtriangleup \dot m_{sys}=0.0\\\\\dot m_{in}=\dot m_{out}\\\\v_1=\frac{RT_1}{P_1}\\\\v_1=\frac{0.3704\times520}{14.7}\\\\\\v_1=13.1026ft^3/lbm\\\\\dot m=\frac{5000/60}{13.1025}\\\\\dot m=6.36\ lbm/s$

Hence, the mass flow rate of the air is 6.36lbm/s

b The specific enthalpy at the exit is defined as the energy balance on the system:

$\dot m_{in}-\dot m_{out}=\bigtriangleup \dot m_{sys}=0.0\\\\\dot m_{in}=\dot m_{out}\\\\\dot W_{in}+ \dot mh_1=\dot Q_{out}+\dot m_2\\\\h_2=\frac{\dot W_{in}-\dot Q_{out}}{\dot m}+h_1\\\\h_2=\frac{700\times 0.7068-10\times 6.36}{6.36}+124.27\\\\h_2=192.06\ Btu/lbm\\\\#at \ h_2=182.06Btu/lbm, T_2=801R=341\textdegree F$

Hence, the temperature at the compressor exit $T_2=341\textdegree F$

5 0

4 years ago