The function of a circuit breaker is to ____

An engine operates on gasoline (LHV=44 MJ/kg) with a brake thermal efficiency of 37.9 % What is the brake specific fuel consumpt

scZoUnD [109]

Answer:

$s =0.21\ kg/Kw.hr$

Explanation:

Given that

Calorific value (CV) = 44 MJ/Kg

CV= 44,000 KJ/kg

Brake thermal efficiency(η) = 37.9 %

We know that

$\eta =\dfrac{BP}{\dot{m_f}\times CV}$

Where BP is the brake power

$\eta =\dfrac{BP}{\dot{m_f}\times CV}$

$0.379 =\dfrac{BP}{\dot{m_f}\times 44000}$

$\dfrac{BP}{\dot{m_f}}=16676$

Brake specific fuel consumption (s)

$s =\dfrac{\dot{m_f}}{BP}$

$s =\dfrac{3600\times \dot{m_f}}{BP}$

$s =\dfrac{3600}{16,676}\ kg/Kw.hr$

$s =0.21\ kg/Kw.hr$

7 0

3 years ago

A CL soil is being used for compacted fill on a project. A sample of the compacted soil with a total volume of 1/30 ft3 weighs 4

Genrish500 [490]

Answer:

A. 0.4

B. 1.003

C. 0.83

Explanation:

The void ratio of a mixture is defined as the ratio of the volume of voids to volume of solids.

Total volume of soil = 1/30 ft3

= 1 ft3/30 * 0.0283 m3/1 ft3

= 9.43 x 10^-4 m3

Mass of water is in the soil = 20% * 4.8

= 0.96 pounds of water

= 0.96 * 0.454

= 0.44 kg

SG = density of substance/density of water

= 2.66 * 1 kg/l

Density of the soil = 2.660 kg/l

Mass of solid = 80 %

= 80% * 4.8 * 0.454

= 1.74 kg

Volume of solids = mass/density

= 1.74/2.66

= 6.63 l

= 6.63 x 10^-4 m3.

The volume of voids is found by adding the volume of water and the volume of air.

Total volume of soil = volume of (solids + voids)

9.43 x 10^-4 = 6.63 x 10^-4 + voids

Volume of voids = 2.8 x 10^-4 m3

A.

Void ratio = volume of void : volume of solids

= 2.8 : 6.63

= 0.4

B.

Y = (1 + w) * Gs * Yw * (1 + e)

Y = moist unit weight

Yw = unit weight of water

w = moisture content of the material

Gs = pecific gravity of the solid

e = void ratio

= (1 + 0.2) * 2.66 * 0.44 * (1 + 0.4)

= 1.003.

C.

gd = Y/(1 + w)

Or

= Gs * Yw * 1/(1 + e)

= 0.83.

6 0

3 years ago

Pls help me answer my module

Otrada [13]

Answer:

Hand tools based on job requirement and its importance and the classification of hand tools according to its function and its importance are discussed below in details.

Explanation:

Hand tools based on work requirement is essential because Every tool is specifically invented for a particular purpose, so picking the accurate tool will also reduce the amount of energy needed to get work done right without causing injury or harm to either the tools or the exterior being worked on.

classifying of hand tools: wrenches, screwdrivers, cutters, striking tools, hammer tool or struck, pliers, vise, clamps, snips, saws, drills, and knives.

4 0

4 years ago

You must yield the right-of-way to all of the following EXCEPT:

Elena-2011 [213]

Answer:

You must yield the right-of-way to a police car, fire engine, ambulance, or other emergency vehicle that uses a siren and flashing lights. Pull as close to the right of the road as possible and stop until the emergency vehicle(s) has passed. However, don't stop in an intersection because that would cause a wreck.

Explanation:

please have a good day. and also mark as brainllest bye

[o]-[o]

\___/

7 0

3 years ago

A quantity of nitrogen gas in a piston–cylinder assembly undergoes a process at a constant pressureof 80 bar from 220 to 300 K.

notka56 [123]

Answer:

work done = 665.12 kJ/k.mol of nitrogen

dQ = 685.905 kJ/k.mol of nitrogen

Explanation:

given data

pressure = 80 bar

temperature t1 = 220 K

temperature t2 = 300 K

solution

first we get here work done as considering ideal gas condition

work done = P (v2-v1 ) = nR (t2-t1)

put here value

work done = 1 × 8.314 ×( 300 - 220 )

work done = 665.12 kJ/k.mol of nitrogen

and

now we get heat transfer by 1st law of thermodynamics that is

heat transfer dQ = dv + dw

dQ = Cv dT + dw

put here value and we get

dQ = $\frac{R}{\gamma -1 }$ × (t2-t1) + 665.12

dQ = $\frac{8.314}{1.4-1}$ × (300-220) + 665.12

dQ = 685.905 kJ/k.mol of nitrogen

8 0

3 years ago

The function of a circuit breaker is to _____.