1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
natita [175]
3 years ago
14

Material selection is one of the design considerations for electronic packages. Explain how each of the material properties belo

w can affect the reliability of a Plastic Quad Flat Package (PQFP) subjected to accelerated thermal cycling (ATC) test. a) Glass Transition Temperature of Encapsulant b) Coefficient of Thermal Expansion of Encapsulant
Engineering
1 answer:
ValentinkaMS [17]3 years ago
7 0

Answer:

The explanations are provided below.

Explanation:

a) The accelerated thermal cycling test is a test that is performed to evaluate the fatigue strength of electronic solder connections. The glass transition temperature given as T_{g} is a frequently used parameter to test the degree of cure of an epoxy encapsulant.

b) The Coefficient of Thermal Expansion of Encapsulant

This is an important parameter to prevent crackling. Crackling occurs when a joint is subjcted to high temperatures during reflow soldering. Thus, the property is important in determining the limits of the joint.

You might be interested in
The moons light-colored highlights are
gulaghasi [49]
The light colored material in areas of the mood is the earliest crust on the moon.
3 0
3 years ago
Calculate the volume of a hydraulic accumulator capable of delivering 5 liters of oil between 180 and 80 bar, using as a preload
Vinil7 [7]

Answer:

1) V_o = 10 liters

2) V_o = 12.26 liters

Explanation:

For isothermal process n =1

V_o =\frac{\Delta V}{(\frac{p_o}{p_1})^{1/n} -(\frac{p_o}{p_2})^{1/n}}

V_o  = \frac{5}{[\frac{72}{80}]^{1/1} -[\frac{72}{180}]^{1/1}}

V_o = 10 liters

calculate pressure ratio to determine correction factor

\frac{p_2}{p_1} =\frac{180}{80} = 2.25

correction factor for calculate dpressure ration  for isothermal process is

c1 = 1.03

actual \ volume = c1\times 10 = 10.3 liters

b) for adiabatic process

n =1.4

volume of hydraulic accumulator is given as

V_o =\frac{\Delta V}{[\frac{p_o}{p_1}]^{1/n} -[\frac{p_o}{p_2}]^{1/n}}

V_o  = \frac{5}{[\frac{72}{80}]^{1/1.4} -[\frac{72}{180}]^{1/1.4}}

V_o = 12.26 liters

calculate pressure ratio to determine correction factor

\frac{p_2}{p_1} =\frac{180}{80} = 2.25

correction factor for calculate dpressure ration  for isothermal process is

c1 = 1.15

actual \volume = c1\times 10 = 11.5 liters

8 0
3 years ago
Consider a 1.80-m-tall man standing vertically in water and completely submerged in a pool. Determine the difference between the
defon

Answer:

17.658 kPa

Explanation:

The hydrostatic pressure of a fluid is the weight of a column of that fluid divided by the base of that column.

P = \frac{weight}{base}

Also, the weight of a column is its volume multiplied by it's density and the acceleration of gravity:

weight = \delta * v * g

Meanwhile, the volume of a column is the area of the base multiplied by the height:

V = base * h

Replacing:

P = \frac{\delta * base * h * g}{base}

The base cancels out, so:

P = \delta * h * g

The pressure depends only on the height of the fluid column, the density of the fluid and the gravity.

If you have two point at different heights (or depths in the case of objects submerged in water) each point will have its own column of fluid exerting pressure on it. Since the density of the fluid and the acceleration of gravity are the same for both points (in the case of hydrostatics density is about constant for all points, it is not the case in the atmosphere), we can write:

\Delta P = \rho * g * (h1 - h2)

We do not know at what depth the man of this problem is, but it doesn't matter, because we know the difference in height of the two points of interes (h1 - h2) = 1.8 m. So:

\Delta P = 9.81 \frac{m}{s^{2} } * 1000 \frac{kg}{m^3} * 1.8 m = 17658 Pa = 17.658 kPa

4 0
3 years ago
Determine the enthalpy, volume and density of 1.0 kg of steam at a pressure of 0.5 MN/m2 and with a dryness fraction of 0.96
Viktor [21]

Answer:

Enthalpy, hsteam = 2663.7 kJ/kg

Volume, Vsteam = 0.3598613 m^3 / kg

Density = 2.67 kg/ m^3

Explanation:

Mass of steam, m = 1 kg

Pressure of the steam, P = 0.5 MN/m^2

Dryness fraction, x = 0.96

At P = 0.5 MPa:

Tsat = 151.831°C

Vf = 0.00109255 m^3 / kg

Vg = 0.37481 m^3 / kg

hf = 640.09 kJ/kg

hg = 2748.1 kJ/kg

hfg = 2108 kJ/kg

The enthalpy can be given by the formula:

hsteam = hf + x * hfg

hsteam = 640.09 + ( 0.96 * 2108)

hsteam = 2663.7 kJ/kg

The volume of the steam can be given as:

Vsteam = Vf + x(Vg - Vf)

Vsteam = 0.00109255 + 0.96(0.37481 - 640.09)

Vsteam = 0.3598613 m^3 / kg

From the steam table, the density of the steam at a pressure of 0.5 MPa is 2.67 kg/ m^3

5 0
3 years ago
The author claims that engineers should always have the final say and last word when it comes to setting safety standards. Selec
Lisa [10]

Answer:

I select false because engineers are not the only thing we have, we have scientists doctors mathematicians and much more to give safety standards

4 0
4 years ago
Read 2 more answers
Other questions:
  • Which of the following is not true about Machine Learning?Machine Learning was inspired by the learning process of human beings.
    11·1 answer
  • 6. Construct a neural network that computes the XOR function of two inputs. Make sure to specify what sort of units you are usin
    7·1 answer
  • An aircraft component is fabricated from an aluminum alloy that has a plane strain fracture toughness of 40 . For an applied str
    10·1 answer
  • The organic acid, ACOOH, reacts reversibly with the alcohol BOH, to form the ester ACOOB according to the stoichiometric equatio
    6·1 answer
  • A standard 20° pressure angle, 20 tooth pinion with a diametral pitch of 12 rotates at 1776 rpm driving a mating gear at 740 rpm
    14·1 answer
  • Ductility (increases/decreases/does not change) with temperature.
    13·1 answer
  • How many extra supports does it take to make a square truss stable?
    10·1 answer
  • What is 222 divided by 11.2
    15·2 answers
  • Tech A says that both OSHA and the EPA can inspect facilities for violations. Tech B says that a shop safety rule does not have
    5·1 answer
  • How is varnished timber shaped and cut?
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!