I need help... What is Torque?

Harvey has an inclination towards astronomy and wants to construct telescope mirrors. Which metal should he use for reflective c

lys-0071 [83]

Answer:

The metal Harvey should use for reflective coatings in telescope mirror is;

C. Aluminum

Explanation:

In a telescope, the mirror of the telescope is usually made of a temperature-resistant and strong glass, while the reflective coating of the mirrors is made usually from aluminum. A protective coating often composed of silicon dioxide is placed n the top of the reflective coating

Aluminum is used in a telescope, rather than the silver, which is the most reflective material, because silver requires special conditions to be able to work, and silver tarnishes when exposed to air containing sulfur, and silver is susceptible to corrode.

3 0

3 years ago

What are the 4 types of electricity?

olchik [2.2K]

Answer:

Fossil Fuels 67% (Non-Renewable Source): Coal 41%, Natural Gas 21% & Oil 5.1%

Renewable Energy 16%

Mainly Hydroelectric 92%: Wind 6%, Geothermal 1%, Solar 1%

Nuclear Power 13%

Explanation:

3 0

3 years ago

Taking the convection heat transfer coefficient on both sides of the plate to be 860 W/m2 ·K, deter- mine the temperature of the

Aleks [24]

Answer:

Hello your question is incomplete attached below is the complete question

answer :

a) 95.80°C

b) 8.23 MW

Explanation:

Convection heat transfer coefficient = 860 W/m^2 . k

a) Calculate for the temp of sheet metal when it leaves the oil bath

first step : find the Biot number 

Bi = hLc / K ------- ( 1 )

where : h = 860 W/m^2 , Lc = 0.0025 m , K = 60.5 W/m°C

Input values into equation 1 above

Bi = 0.036 which is < 1 ( hence lumped parameter analysis can be applied )

next : find the time constant 

t ( time constant ) = h / P*Cp *Lc --------- ( 2 )

where : p = 7854 kg/m^3 , Lc = 0.0025 m , h = 860 W/m^2, Cp = 434 J/kg°C

Input values into equation 2 above

t ( time constant ) = 0.10092 s^-1

Determine the elapsed time

T = L / V = 9/20 = 0.45 min

∴ temp of sheet metal when it leaves the oil bath

= (T(t) - 45 ) / (820 - 45) = e^-(0.10092 * 27 )

T∞ = 45°C

Ti = 820°C

hence : T(t) = 95.80°C

b) Calculate the required rate of heat removal form the oil

Q = mCp ( Ti - T(t) ) ------------ ( 3 )

m = ( 7854 *2 * 0.005 * 20 ) = 26.173 kg/s

Cp = 434 J/kg°C

Ti = 820°C

T(t) = 95.80°C

Input values into equation 3 above

Q = 8.23 MW

6 0

3 years ago

Are teen courts a good idea

Zolol [24]

Idea about teen courts is given below

Explanation:

1.Teen courts are spreading rapidly across the United States. Many people view them as a cost-effective alternative to traditional juvenile court for some young offenders.

2.Teen courts are generally used for younger juveniles (ages 10 to 15), those with no prior arrest records, and those charged with less serious law violations (e.g., shoplifting, vandalism, and disorderly conduct). Typically, young offenders are offered teen court as a voluntary alternative in lieu of more formal handling by the traditional juvenile justice system

3.Teen courts differ from other juvenile justice programs because young people rather than adults determine the disposition, given a broad array of sentencing options made available by adults overseeing the program.

4.Teen court defendants may go through an intake process, a preliminary review of charges, a court hearing, and sentencing, as in a regular juvenile court. In a teen court, however, other young people are responsible for much of the process. Charges may be presented to the court by a 15-year-old “prosecutor.” Defendants may be represented by a 16-year-old “defense attorney.” Other youth may serve as jurors, court clerks, and bailiffs.

5.In some teen courts, a youth “judge” (or panel of youth judges) may choose the best disposition or sanction for each case. In a few teen courts, youth even determine whether the facts in a case have been proven by the prosecutor (similar to a finding of guilt).

6.Adults are also involved in teen courts. They often administer the programs, and they are usually responsible for essential functions such as budgeting, planning, and personnel.

7.Teen courts are seen as a potentially effective alternative to traditional juvenile courts staffed with paid professionals such as lawyers, judges, and probation officers. Teen court advocates also point out that the benefits extend beyond defendants. Teen courts may benefit the volunteer youth attorneys and judges, who probably learn more about the legal system than they ever could in a classroom. The presence of a teen court may also encourage the entire community to take a more active role in responding to juvenile crime. Teen courts offer at least four potential benefits:

6 0

3 years ago

Analyze the rate of heat transfer through a wall of an industrial furnace which is constructed from 0.15-m-thick fireclay brick

Simora [160]

Answer:

1700 W

Explanation:

The heat transfer rate P = kA(T - T')/d where k = thermal conductivity of wall = 1.7 W/m-K, A = area of wall = 0.5 m × 1.2 m = 0.6 m², T = temperature of inner surface = 1400 K, T = temperature of outer surface = 1150 K and d = thickness of wall = 0.15 m

So, P = kA(T - T')/d

substituting the values of the variables into the equation, we have

P = 1.7 W/m-K × 0.6 m²(1400 K - 1150 K)/0.15 m

P = 1.7 W/m-K × 0.6 m² × 250 K/0.15 m

P = 255 Wm/0.15 m

P = 1700 W

So, the heat transfer rate through the wall is 1700 W

4 0

3 years ago