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
mina [271]
3 years ago
14

Which of the following is correct regarding the principal stresses and maximum in-plane shear stresses? a. Principal stresses ca

nnot be negative. b. The shear stress over principal stress planes is always zero.c. A principal stress plane can be reached by rotating the maximum in-plane shear stress plane 90° in the clockwise direction. d. The maximum in-plane shear stress is always smaller than principal stresses.
Engineering
1 answer:
ziro4ka [17]3 years ago
4 0

Answer:

option B.

Explanation:

The correct answer is option B.

Principal stress is the maximum normal stress a body can have. In principal stress, there is purely normal stress. On principal plane shear stress is zero.

In-plane shear stress are the shear stress which is acting on the plane.

The statement which is correct regarding principle plane and shear stress is that The shear stress over principal stress planes is always zero.

You might be interested in
Unless a structural element is intended to be battered, sloped, or cambered (or some other non-conforming position), wood, steel
SSSSS [86.1K]

Answer:

stability; resistance; rigidity.

Explanation:

Okay, let us fill in the gap in the question above. Please note that the capitalized words are the missing words to fill in the gap.

"Unless a structural element is intended to be battered, sloped, or cambered (or some other non-conforming position), wood, steel, and concrete should always be installed and maintained STABILITY , RESISTANCE , and RIGIDITY. These conditions are critical in order to ensure maximum stability, structural performance and user satisfaction."

This question has to deal with buildings or say structural (civil) engineering. The definition to the missing words are given below:

STABILITY: Stability occurs when we have the center of gravity coinciding with the base of the structure.

RESISTANCE : Resistance simply means the 'tension' that is is how much the structure can resist an applied force.

RIGIDITY : RIGIDITY can also be associated with resistance and it is the property of a structure to resist bending.

5 0
3 years ago
Plz help me
Dmitrij [34]

As much as the human and physical capital in economy increases, there is a decrease in the marginal gain in economic growth that will diminish.

<u>Explanation:</u>

Low-income countries might have an advantage achieving greater worker productivity and economic growth in the future as their economic growth is faster than the high - income countries.

As much as the human and physical capital in economy increases, there is a decrease in the marginal gain in economic growth that will diminish. And this is called, the laws of diminishing returns.

Secondly, low - income countries find it easier in developing technologies than the high - income technologies especially countries like India and China.

High - income countries put effort in inventing new technologies, whereas low - income countries just improve and improvise their technology.

3 0
4 years ago
The two boxcars A and B have a weight of 20000lb and 30000lb respectively. If they coast freely down the incline when the brakes
kolbaska11 [484]

Answer:

T=5.98 kips

Explanation:

First, introduce forces, acting on both cars:

on car A there are 4 forces acting: gravity force mA*g, normal reaction force, friction force and force T- it represents the interaction between cars A and B. On car B, there are three forces acting: gravity force, normal reaction force and force T. Note, that force T is acting on both cars, but it has opposite direction. Force T, acting on car A has direction, opposite to the friction force, whether the T, acting on B, is directed backwards- in the same direction with the friction force. Note, that both cars have the same acceleration, which is directed backwards.

Once the forces were established, we can write components of the Second Newtons Law on vertical and horizontal axes, considering that horizontal axis is directed backwards- in the same direction with the acceleration:

For car A on the vertical axis the equation is: -mAg+NA=0

For car A on the horizontal axis, the equation is: Ffr-T=mAa

For car B, on the vertical axis the equation is: -mBg+NB=0

For car B, on the horizontal axis, the equation is: T=mBa

We need to solve these equations to find force T, knowing that Ffr=μmAg, where

After the transformations, the equations for acceleration and force in the coupling will be:

a=(μmAg)/(mA+mB)=6.43 ft/s2- note, that the given answer is not correct for the given numerical values;

and force T: T=μmAmBg/(mA+mB)=6.0 kips- note, that the force answer is in line with the given numerical value

5 0
4 years ago
Very thin films are usually deposited under vacuum conditions to prevent contamination and ensure that atoms can fly directly fr
katrin [286]

Answer:

a. 9947 m

b. 99476 times

c. 2*10^11 molecules

Explanation:

a) To find the mean free path of the air molecules you use the following formula:

\lambda=\frac{RT}{\sqrt{2}\pi d^2N_AP}

R: ideal gas constant = 8.3144 Pam^3/mol K

P: pressure = 1.5*10^{-6} Pa

T: temperature = 300K

N_A: Avogadros' constant = 2.022*10^{23}molecules/mol

d: diameter of the particle = 0.25nm=0.25*10^-9m

By replacing all these values you obtain:

\lambda=\frac{(8.3144 Pa m^3/mol K)(300K)}{\sqrt{2}\pi (0.25*10^{-9}m)^2(6.02*10^{23})(1.5*10^{-6}Pa)}=9947.62m

b) If we assume that the molecule, at the average, is at the center of the chamber, the times the molecule will collide is:

n_{collision}=\frac{9947.62m}{0.05m}\approx198952\  times

c) By using the equation of the ideal gases you obtain:

PV=NRT\\\\N=\frac{PV}{RT}=\frac{(1.5*10^{-6}Pa)(\frac{4}{3}\pi(0.05m)^3)}{(8.3144Pa\ m^3/mol\ K)(300K)}=3.14*10^{-13}mol\\\\n=(3.14*10^{-13})(6.02*10^{23})\ molecules\approx2*10^{11}\ molecules

5 0
3 years ago
What's the third pedal for in a vehicle​
pshichka [43]

Manual Transmission Cars typically have 3 pedals which are

1) Brake Pedal

2) Gas / Acceleration Pedal

3) Clutch Pedal

6 0
4 years ago
Other questions:
  • Why should engineers avoid obvious patterns?
    13·2 answers
  • Question 4 (1 point)
    8·1 answer
  • What is your employer required to have on fixed ladders that extend more than 24 feet in the workplace?
    15·2 answers
  • Shear plane angle and shear strain: In an orthogonal cutting operation, the tool has a rake angle = 16°. The chip thickness befo
    7·1 answer
  • A flow of 12 m/s passes through a 6 m wide, 2 m deep rectangular channel with a bed slope of 0. 001. If the mean velocity of flo
    12·1 answer
  • Drag each label to the correct location on the image.
    5·2 answers
  • How did humans create a space suit without ever going. How did we know spaces conditions?
    5·2 answers
  • What form of joining uses heat to create coalescence of the materials?
    7·1 answer
  • Determine the maximum height (in inches) that a lift pump can raise water (0.9971 g/ml) from a well at normal atmospheric pressu
    10·1 answer
  • PLEASE FIX THIS LUA SCRIPT
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!