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2 years ago

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If the power to a condensing unit has been turned off for an extended period of time, the _________________________ should be en

ergized first for the recommended time to protect the compressor from liquid floodback. A. blower motor B. thermostat C. crankcase heater D. condenser fan motor

1 answer:

Mama L [17]2 years ago

7 0

Answer:

C. Crankcase heater

Explanation:

The crankcase heater of the compressor was developed to mitigate the problematic variation of temperature on the in and out sides of the crankcase that has the capacity to change the physical states of the refrigerant and oil, cause them migrate and possibly mix together. It does so by allowing the regulation of the temperature on the inside of the crankcase

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python Write a program that asks a user to type in two strings and that prints •the characters that occur in both strings. •the

Yuliya22 [10]

Answer:

see explanation

Explanation:

#we first get the elements as inputs

x = input("enter string A :")

y = input("enter string B :")

#then we make independent sets with each

x = set(x)

y = set(y)

#then the intersection of the two sets

intersection = set.intersection(x,y)

#another set for the alphabet

#we use set.difference to get the elements present in x and not in y, and

#viceversa, finally we get the difference between the alphabet and the #intersection of the elements in our strings

z = set('abcdefghijklmnopqrstuvwxyz')

print('\nrepeated :\n',intersection)

print('differences :\n',' Items in A and not B\n',

set.difference(x,y),'\nItems in B and not A\n',

set.difference(y,x))

print('\nItems in neither :\n',set.difference(z,intersection))

8 0

3 years ago

What are the advantages and disadvantages of a mine heardgear

Irina18 [472]

Answer:

If there is a shaft with headgear, then mining can take place until that depth of the shaft. If it is accessed horizontal Adits, it can mine until the lowest Adit from upwards. If it is accessed decline, the development and mining can continue so long as economic exploitation is possible.

Explanation:

What are the disadvantages of mining headgear? They totally cut off your vision of anything above your head. They are hot, most of the time

7 0

1 year ago

Convert 850 nm wavelength into frequency, eV, wavenumber, joules and ergs.

Sholpan [36]

Answer:

Frequency = $3.5294\times 10^{14}s^{-1}$

Wavenumber = $1.1765\times 10^6m^{-1}$

Energy = $2.3365\times 10^{-19}J$

Energy = 1.4579 eV

Energy = $2.3365\times 10^{-12}erg$

Explanation:

As we are given the wavelength = 850 nm

conversion used : $(1nm=10^{-9}m)$

So, wavelength is $850\times 10^{-9}m$

The relation between frequency and wavelength is shown below as:

$Frequency=\frac{c}{Wavelength}$

Where, c is the speed of light having value = $3\times 10^8m/s$

So, Frequency is:

$Frequency=\frac{3\times 10^8m/s}{850\times 10^{-9}m}$

$Frequency=3.5294\times 10^{14}s^{-1}$

Wavenumber is the reciprocal of wavelength.

So,

$Wavenumber=\frac{1}{Wavelength}=\frac{1}{850\times 10^{-9}m}$

$Wavenumber=1.1765\times 10^6m^{-1}$

Also,

$Energy=h\times frequency$

where, h is Plank's constant having value as $6.62\times 10^{-34}J.s$

So,

$Energy=(6.62\times 10^{-34}J.s)\times (3.5294\times 10^{14}s^{-1})$

$Energy=2.3365\times 10^{-19}J$

Also,

$1J=6.24\times 10^{18}eV$

So,

$Energy=(2.3365\times 10^{-19})\times (6.24\times 10^{18}eV)$

$Energy=1.4579eV$

Also,

$1J=10^7erg$

So,

$Energy=(2.3365\times 10^{-19})\times 10^7erg$

$Energy=2.3365\times 10^{-12}erg$

5 0

3 years ago

How many people made machines

olganol [36]

Answer:

The total number of people whom have made machines is not a recorded figure? Need to be more specific :/

Explanation:

Sorry not very helpful, your question is REALLY broad

3 0

2 years ago

Read 2 more answers

Air at 80 kPa and 10Â°C enters an adiabatic diffuser steadily with a velocity of 150 m/s and leaves with a low velocity at a pre

il63 [147K]

Answer:

The exit temperature is 293.74 K.

Explanation:

Given that

At inlet condition(1)

P =80 KPa

V=150 m/s

T=10 C

Exit area is 5 times the inlet area

Now

$A_2=5A_1$

If consider that density of air is not changing from inlet to exit then by using continuity equation

$A_1V_1=A_2V_2$

So $A_1\times 150=5A_1V_2$

$V_2=30$ m/s

Now from first law for open system

$h_1+\dfrac{V_1^2}{2}+Q=h_2+\dfrac{V_2^2}{2}+w$

Here Q=0 and w=0

$h_1+\dfrac{V_1^2}{2}=h_2+\dfrac{V_2^2}{2}$

When air is treating as ideal gas

$h=C_pT$

Noe by putting the values

$h_1+\dfrac{V_1^2}{2}=h_2+\dfrac{V_2^2}{2}$

$1.005\times 283+\dfrac{150^2}{2000}=1.005\times T_2+\dfrac{30^2}{2000}$

$T_2=293.74K$

So the exit temperature is 293.74 K.

7 0

3 years ago