(Please help me this needs to be done ASAP )

How large an expansion gap should be left between steel railroad rails if they may reach a maximum temperature 30.0°C greater th

irina [24]

Answer:

Explanation:

<u>Thermal Expansion</u>

It's the tendency that materials have to change its size and/or shape under changes of temperature. It can be in one (linear), two (surface) or three (volume) dimensions.

The formula to compute the expansion of a material under a change of temperature from $T_o$ to $T_f$ is given by.

$\Delta L=L_o.\alpha .(T_f-T_o)$

Where Lo is the initial length and $\alpha$ is the linear temperature expansion coefficient, which value is specific for each material. The data provided in the problem is as follows:

$L_o=30\ m,\ T_f-T_o=30^oC,\ \alpha=13\times 10^{-6}\ ^oC^{-1}$

Computing the expansion we have

$\Delta L=30\times 13\times 10^{-6}(30)=0.0117=1.17\ cm$

The expansion gap should be approximately 1.2 cm

6 0

3 years ago

Zinc is best used for making<br><br> a. glass<br> b. walls<br> c. screws<br> d. fertilizers

Levart [38]

C. zinc is best used for making screws. Zinc is best used for making alloys, anything made from 55% or 95% copper more then likely contain zinc

5 0

4 years ago

(b) Assuming h is small in comparison to the radius of the Earth, show that the difference in free-fall acceleration between two

Sholpan [36]

Vertical distance h isΔg $=\frac{-2GM}{ RE^{3} }$

<h3>What is vertical?</h3>

The distance between two vertical places is known as the vertical separation or vertical distance. There are numerous ways to express vertical position using vertical coordinates, including depth, height, altitude, elevation, etc.
The formula for vertical distance from the ground is y = - g * t2 / 2, where g is the acceleration of gravity and h is a height.
The vertical distance between the measurement point and the point of observation on Earth's surface. Altitude is the vertical distance from the measurement place to mean sea level.

Assuming h is small in comparison to the radius of the Earth, show that the difference in free-fall acceleration between two points separated by vertical distance h isΔg = (2GMeH) / RE³:

Given:

Separated between two points=h

And, h∠∠ $R_{E}$ ( $R_{E}$ = radius of the Earth)