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3 years ago

Circuit breakers and disconnect switches are examples of what

Engineering

1 answer:

kotykmax [81]3 years ago

3 0

Answer: Energy-Isolating devices

Explanation:

Energy-isolating devices are used to restrict the flow or transmission of energy (electricity in this case) by physical means therefore it includes manually operated devices such as a manually operated electrical circuit breakers and disconnect switches.

Manually controlled circuit breakers restrict the flow of electricity if the current is too much and the flow will remain restricted until the switch is flipped back to allow electricity to flow while a Disconnect switch works by shutting down the circuit when a problem is detected.

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Technician A says ASE certification is mandatory in all 50 states before performing an automotive repair for pay. Technician B s

yuradex [85]

Answer:

Technicians A is correct

Explanation:

According to ASE ( Automotive service excellence) "Certification credentials are valid for five years. If it has been five years or more since you took a test, it’s time to register for the corresponding Recertification Test. The five-year requirement ensures certified professionals are current in this rapidly changing industry."

This counters the claim of technician B who say the programs must be reviewed every three years , and ASE sends you reminders before your credentials expire.

5 0

3 years ago

The rate of energy transfer by work is called power. a)-True b)-False

Pie

Answer:

Yes the statement is true.

Explanation:

Power is defined as the rate at which energy is transferred by an object on account of work done.

Mathematically

$Power=\frac{dE}{dt}$

An object that does work loses it's energy while an object on which work is done gains energy.

Power is often dependent on the type of energy transfer thus we have Electrical Power, Mechanical Power depending on the type of energy involved in the system.

Concept of power is important since it gives us a measure of how fast energy can be derived to given to a system.

5 0

3 years ago

Carbon dioxide (CO2) expands isothermally at steady state with no irreversibilities through a turbine from 10 bar, 500 K to 2 ba

xenn [34]

Answer:

The answer to the question above is = 152.02 KJ/Kg

Explanation:

Given:

Temperature at first state, (T $1$ )= 500k

Temperature at second state, (T $2$ )= 500k

The above explains an isothermal process as a thermodynamic process,in which the temperature of the system remains constant

Pressure at first state, (p $1$ ) = 10 bar

Pressure at second state, (p $2$ ) = 2 bar

The heat transfer=

Qrev/m= T x [s(T $2$ ) - s(T $1$ ) - R ㏑ (p $2$ ÷ p $1$ )]

Isothermal means the temperature does not change, while Expansion means the volume has increased.

For the internal isothermal process:

Qrev/m= T x [- R ㏑ (p $2$ ÷ p $1$ )]

= 500 x - (8.314 ÷ 44.01) x In (2 ÷ 10) = 152.02 KJ/Kg

Energy equation at turbine is for the internally reversible isothermal process is:

Q-w = m [( (V $2$ ²- V $1$ ²) ÷ 2) + g ( Z $2$ - Z $1$ )]

where w= the most efficient work possible in J

Neglecting the effect of both potential and kinetic energy

(w/ m) = Qrev/ m

= 152.02 KJ/Kg

4 0

3 years ago

1. Copy the file Pay.java (see Code Listing 1.1) from the Student CD or as directed by your instructor. 2. Open the file in your

Mrac [35]

Answer:

Code Listing 1.1 (Pay.java)

import java.util.Scanner; // Needed for the Scanner class

/**

This program calculates the user's gross pay.

public class Pay

{

public static void main(String[] args)

{

// Create a Scanner object to read from the keyboard. Scanner keyboard = new Scanner(System.in);

// Identifier declarations

double hours; // Number of hours worked

double rate; // Hourly pay rate double pay; // Gross pay

// Display prompts and get input. System.out.print("How many hours did you work? "); hours = keyboard.nextDouble();

System.out.print("How much are you paid per hour? ");

rate = keyboard.nextDouble();

// Perform the calculations. if(hours <= 40)

pay = hours * rate;

else

pay = (hours - 40) * (1.5 * rate) + 40 * rate;

// Display results. System.out.println("You earned $" + pay);

}

Code Listing 1.2 (SalesTax.java)

import java.util.Scanner; // Needed for the Scanner class

/**

This program calculates the total price which includes

sales tax.

public class SalesTax

{

public static void main(String[] args)

{

// Identifier declarations final double TAX_RATE = 0.055; double price;

double tax

double total; String item;

// Create a Scanner object to read from the keyboard. Scanner keyboard = new Scanner(System.in);

// Display prompts and get input. System.out.print("Item description: "); item = keyboard.nextLine(); System.out.print("Item price: $");

price = keyboard.nextDouble();

// Perform the calculations. tax = price + TAX_RATE;

totl = price * tax;

// Display the results. System.out.print(item + " $"); System.out.println(price); System.out.print("Tax $"); System.out.println(tax); System.out.print("Total $"); System.out.println(total);

}

5 0

4 years ago

A steel bar 100 mm long and having a square cross section 20 mm x 20 mm is pulled in

Ierofanga [76]

Answer:

222.5 Gpa

Explanation:

From definition of engineering stress, $\sigma=\frac {F}{A}$