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
kondaur [170]
3 years ago
8

A rectangular aluminum bar (~1.52.1 cm in cross section) and a circular steel rod (~1 cm in radius) are each subjected to an axi

al force of 20 kN. Assuming that both are 30 cm long in their unloaded configuration, find (a) the stress in each, (b) the extensional strain in each, and (c) the amount of lengthening in each. Let E¼70 GPa for aluminum and 200 GPa for steel.
Physics
1 answer:
garri49 [273]3 years ago
4 0

Answer:

(a) Aluminium= 6.3492*10^{7} N/m^{2}  , steel=6.366*10^{7} N/m^{2}

(b) Aluminium=0.0907*10^{-2}  , steel=0.0318*10^{-2}

(c) Aluminium= 0.2721 cm, Steel= 0.009549cm

Explanation:

(a)

For aluminium bar, stress, \sigma is given by  

\sigma= \frac {F}{A} where A is cross-sectional area of bar and F is force applied

Therefore, \sigma= \frac {20*10^{3}}{1.5*10^{-2}*2.1*10^{-2}}=6.3492*10^{7} N/m^{2}

For steel rod,  

\sigma= \frac {F}{A}= \frac {20*10^{3}}{ \pi R^{2}}=\frac {20*10^{3}}{ \pi 0.01^{2}}=6.366*10^{7} N/m^{2}

(b)

Strain, \epsilon in aluminium is given by

\epsilon = \frac { \sigma}{E}where E is Young’s Modulus

\epsilon= \frac {6.39*10^{7}}{70*10^{9}}=0.0907*10^{-2}

For steel rod

\epsilon = \frac { \sigma}{E}

\epsilon= \frac {6.37*10^{7}}{200*10^{9}}=0.0318*10^{-2}

(c)

Strain, \epsilon is given by  

\epsilon = \frac {Elongation}{original length} hence the change in length is product of original length and \epsilon

For aluminium rod,

Elongation= 30*0.0907*10^{-2}=0.2721 cm

For steel rod

Elongation= 30*0.0318*10^{-2}= 0.009549 cm

You might be interested in
Which of the following statements is FALSE regarding the law of conservation of energy?
Jobisdone [24]

Answer:

D

Explanation:

because it doesn't agree with the law of definite proportion

and energy can niether be created nor destroyed but can be transformed from one form to another

5 0
3 years ago
What is direct result of having greenhouse gases in the atmosphere?​
11111nata11111 [884]
Earths atmosphere heats up polars melt
4 0
3 years ago
In which test did the air parcel rise the highest? Is there a pattern in the relationship between starting air temperature and p
wel

Answer:

xitxitx

Explanation:

ufxigxigxitcutcocyocoycitcotcitcohcohxitxigcigxigxkgxigxigxigxigxigxigxitx8y

5 0
3 years ago
Please answer the number 5 6 and 7. I don't know what to do its our hw in physics. (new lesson as well)
Aleks04 [339]

From the picture, I see that you had no trouble at all with #4.
Well, #5, 6, and 7 are easily handled in exactly the same way.

Just as you did with #4, please sketch these on paper
as I walk you through the solutions.  That'll help you see
immediately what's going on.

#5.b).
Traveling east at 3 m/s for 4 seconds,
he covers  (3 m/s) x (4 sec) = 12 meters.

Traveling south at 5 m/s for 2 seconds,
he covers (5 m/s) x (2 sec) = 10 meters.

The total distance he covers is  (12m + 10m) = 22 meters.

#5.c).
Average speed (scalar)

                           = (distance covered)/(time to cover the distance)

                           = (22 meters)/(6 sec) = 3-2/3 m/s .

#5.d).
Displacement (vector)

                       = distance between the start-point and the end-point,
                          regardless of the route traveled,
                      
  in the direction from the start-point to the end-point.

Distance from the start-point to the end-point =

               √(12² + 10²) = √(144 + 100) = √(244) = 15.62 meters

in the direction of  arctan(10/12) south of east

                             =  39.8° south of east.
 
#5.e).
Average velocity (vector) =

             (displacement vector) / (time)

         =  15.62 meters directed 39.8° south of east / 6 seconds

         =  2.603 m/s directed 39.8° south of east.

 #6).
Magnitude = √(5.2² + 2.1²) = √(27.04 + 4.41) = √31.45 = 5.608 km.

Direction = arctan(5.2/2.1) south of east

                =   68° south of east  =  158° bearing . 

#7).
Magnitude = √(39² + 57²) = √(1521 + 3249) = √( 4770)

                                                                         =  69.07 m/s .

Direction = arctan (57/39) south of west

               =   55.6° south of west

                    Bearing = 214.4°

                    Compass: 0.65° past "southwest by south".  


I'm grateful for the privilege and opportunity to practice my math,
and I shall cherish the bounty of 5 points that came with it.

8 0
4 years ago
g a mass of 1.3 kg is pushed horizontally against a massless spring with a spring constant of 58 n/m until the spring compresses
ExtremeBDS [4]

Answer: 1.102\ J

Explanation:

Given

Mass m=1.3\ kg

Spring constant k=58\ N/m

Compression in the spring x=19.5\ cm\ or\ 0.195\ m

When the mass leaves the spring, the elastic potential energy of spring is being converted into kinetic energy of mass i.e.

\Rightarrow \dfrac{1}{2}kx^2=\dfrac{1}{2}mv^2\\\\\Rightarrow \dfrac{1}{2}\cdot 58\cdot (0.195)^2=\dfrac{1}{2}mv^2\\\\\Rightarrow \dfrac{1}{2}mv^2=1.102\ J

The kinetic energy of the mass is 1.102 J.

5 0
3 years ago
Other questions:
  • An astronomer wants to visualize the relative distances between planets in our solar system. A biologist wants to examine the br
    15·2 answers
  • Two fans are watching a baseball game from different positions. One fan is located directly behind home plate, 18.3 m from the b
    10·1 answer
  • 8. two +1 C charges are separated by 3000m. What is the magnitude of the electric force between them?
    13·1 answer
  • a rock is at the top of a 20 meter tall hill the rock has a mass of 10 kg how much potential does it have
    9·1 answer
  • A 25.0 kg box of textbooks rests on a loading ramp that makes an angle α with the horizontal. The coefficient of kinetic frictio
    7·1 answer
  • Colin knows that as water moves through the water cycle, condensation also takes place. Condensation occurs when water vapor coo
    7·1 answer
  • Study the distance-time graph, showing the distances that eight different things cover in 120 seconds or less. The letters below
    11·1 answer
  • Which techniques can scientists use to determine the characteristics of Earth's layers? Select the two correct answers.
    12·2 answers
  • A tight knot can be easily opens by using a longer spanner. Give reasons
    14·1 answer
  • Which color of visibe light has a lower frequency than orange light
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!