An electrical device is insulated on all sides except one face. That face is bonded to a 4mm thick aluminum plate which is cooled by air. The electrical device dissipates 10^4 W m2 The resistance of the joint between the device and aluminum plate is 0.5E-4 m2K W The conductivity of the aluminum is 238 W mK The temperature of the air is 278 K and the convection coefficient from the aluminum plate to the air is 100 W m2K What is the operating temperature of the device

t₁ = 378.668 K

Explanation:

From the given information:

The heat dissipated (q) from the electrical device =

The contact resistance between device and aluminium;

(R_{const} ) = 0.5× 10⁻⁴ m² K/W

Conductivity of aluminum (k)  = 238 \ W/mK

The thickness of aluminum plate (L) = 0.004 m

Convection coefficient (h) = 100 \ W/m^2 K

Surrounding temperature (t_2) = 278 \ k

According to Fourier's law of heat conduction.

t₁ = 378.668 K

True, a retractable service pit cover can help other shop employees from falling into the pit while another technician is in the pit servicing a car.

Retractable service pit cover is a special cover made to cover service pit which aid inspection and repair of vehicle in an auto workshop.

In conclusion, the retractable service pit cover help other shop employees from falling into the pit even if they are aware of the structure.

Learn more about retractable service pit in picture attached

Code:

#include <iostream>

using namespace std;

int main()

{

  int Car_Year;

  cout<<"Please Enter the Car Model."<<endl;

  cin>>Car_Year;    

 if (Car_Year<1967)

 {

cout<<"Few safety features."<<endl;

 }

else if (Car_Year>1971 && Car_Year<=1991)

{

cout<<"Probably has head rests."<<endl;

}

else if (Car_Year>1991 && Car_Year<=2000)

{

cout<<"Probably has antilock brakes."<<endl;

}

else if (Car_Year>2000)

{

cout<<"Probably has airbags."<<endl;

  }

else

{

cout<<"Invalid Selection."<<endl;

}

  return 0;

}

Output:

Please Enter the Car Model.

1975

Probably has head rests.

Please Enter the Car Model.

1999

Probably has antilock brakes.

Please Enter the Car Model.

2005

Probably has airbags.

Please Enter the Car Model.

1955

Few safety features.

Explanation:

We were required to implement multiple If else conditions to assign car model year with the corresponding features of the car.

The code is tested with a wide range of inputs and it returned the same results as it was asked in the question.

"Test Phase " is the correct choice.

Explanation:

The following code or the program will be used

Explanation:

def readFile(filename):

   dict = {}

   with open(filename, 'r') as infile:

       lines = infile.readlines()

       for index in range(0, len(lines) - 1, 2):

           if lines[index].strip()=='':continue

           count = int(lines[index].strip())

           name = lines[index + 1].strip()

           if count in dict.keys():

               name_list = dict.get(count)

               name_list.append(name)

               name_list.sort()

           else:

               dict[count] = [name]

           print(count,name)

   return dict

def output_keys(dict, filename):

   with open(filename,'w+') as outfile:

       for key in sorted(dict.keys()):

           outfile.write('{}: {}\n'.format(key,';'.join(dict.get(key

           print('{}: {}\n'.format(key,';'.join(dict.get(key  

def output_titles(dict, filename):

   titles = []

   for title in dict.values():

       titles.extend(title)

   with open(filename,'w+') as outfile:

       for title in sorted(titles):

           outfile.write('{}\n'.format(title))

           print(title)

def main():

   filename = input('Enter input file name: ')

   dict = readFile(filename)

   if dict is None:

       print('Error: Invalid file name provided: {}'.format(filename))

       return

   print(dict)

   output_filename_1 ='output_keys.txt'

   output_filename_2 ='output_titles.txt'

   output_keys(dict,output_filename_1)

   output_titles(dict,output_filename_2)  

main()

Energy equation from this week’s notes, your answer from #5, and Plank’s constant (6.63E-34) to find the approximate energy of this photon

Explanation:

1.The amount of energy in those photons is calculated by this equation, E = hf, where E is the energy of the photon in Joules; h is Planck's constant, which is always 6.63 * 10^-34 Joule seconds; and f is the frequency of the light in hertz

2.The first is Planck's equation, which was proposed by Max Planck to describe how energy is transferred in quanta or packets. Planck's equation makes it possible to understand blackbody radiation and the photoelectric effect. The equation is:

E = hν

where

E = energy

h = Planck's constant = 6.626 x 10-34 J·s

ν = frequency

x=float(input("Enter a number: "))

sub=(x-int(x))

print(sub)

Explanation:

Got it Right

B ). When cleaning a vessel, use regular  household detergents and cleaners.

Explanation:

Boat cleaning or vessel cleaning is a tedious job. It takes a lot of hard work to clean a vessel. We have to be careful while maintaining the vessel.

The products that we use to clean and maintain the vessels needs to chosen carefully. Many boat cleaning products have adverse effects on the marine life and aquatic animals. it also tends to pollute the water bodies.

These products may be corrosive in nature, toxic or poisonous.

So we must use the regular household detergents and cleaners to clean our vessels. The regular detergents do not cause any harm to the nature and the water bodies.

We can use phosphate free no detergent soaps which may include citrus based soap or vegetable based soaps.

Therefore, while cleaning or maintaining vessels , use the regular household detergents and cleaners.  

Thus option (B) is correct.

Learn more :

link

understanding others first before starting to explain your own point

Explanation:

Stephen covey believes the key to effective communication is understanding others first before starting to explain your own point. Communication is an important skill in life, in which one must have a good character in order to communicate effectively.