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3 years ago

Why do wires hang loosely during summer?

Engineering

1 answer:

Stella [2.4K]3 years ago

6 0

Answer:

due to the expansion process and they contract during winter due to the contraction process. Explanation: Electric cables are the solids which exhibit the property of contraction and expansion.

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The water requirement for Class H cement is 38% (i.e.,water (%) by weight of cement),whereas the water requirement for barite is

Vikentia [17]

Answer:

weight of barite = 398.4355 kg

Explanation:

Solution:- The values given in the question are as follows:

water requirement for H class cement = 38% by weight of cement

water requirement for barite = 2.4 gal / 100 lbm

H class cement slurry = 15.7 lbm/gal

one sack of cement = 50 kg or 110.231 lbm

one sack of cement require water = (38/100)*110.231

one sack of cement require water = 41.8877 gal

water required 100 lbm barite = 2.4 gal

or water required barite = 2.4% by weight of barite

H class cement slurry = (weight of cement + weight of barite)/total weight of water

15.7 =(110.231 + weight of barite)/(water required one sack of cement + 2.4%*weight of barite)

15.7 = 110.231 + (weight of barite)/(41.887 + 0.024*weight of barite)

15.7*41.8877 + 15.7*0.024*weight of barite = 110.231 + weight of barite

657.6368 + 0.3768*weight of barite = 110.231 + weight of barite

547.4058 =0.6232*weight of barite

weight of barite = 878.379 lbm or 878.4 lbm

weight of barite = 398.4355 kg

7 0

4 years ago

Bebe receives a letter from the FBI stating that she is wanted for a crime. The letter says she must send her Social Security nu

Gala2k [10]

Answer:

Explanation:

This helps to make sure that she gets direct response from the sender as to what crime she has committed.

4 0

2 years ago

What kinds of problems or projects would a mechanical engineer work on?

Mademuasel [1]

Answer:

Design power producing machines like electric generators, internal combustion engines, turbines and power using machines like refrigiration or air conditioning. And alot like elevators or such.

Explanation:

If that is what your asking for? Sorry if its not what you wanted. In genral all hard work science and maths

3 0

3 years ago

For the speed equation along centerline of a diffuser, calculate the fluid acceleration along the diffuser centerline as a funct

Marrrta [24]

Answer:

$a = v\cdot \frac{dv}{dx}$ , $v (x) = v_{in}\cdot \left[1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}}-1 \right)\cdot x \right]^{-1}$ , $\frac{dv}{dx} = -v_{in}\cdot \left(\frac{1}{L}\right) \cdot \left(\frac{v_{in}}{v_{out}}-1 \right) \cdot \left[1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}} -1 \right) \cdot x \right]^{-2}$

Explanation:

Let suppose that fluid is incompressible and diffuser works at steady state. A diffuser reduces velocity at the expense of pressure, which can be modelled by using the Principle of Mass Conservation:

$\dot m_{in} - \dot m_{out} = 0$

$\dot m_{in} = \dot m_{out}$

$\dot V_{in} = \dot V_{out}$

$v_{in} \cdot A_{in} = v_{out}\cdot A_{out}$

The following relation are found:

$\frac{v_{out}}{v_{in}} = \frac{A_{in}}{A_{out}}$

The new relationship is determined by means of linear interpolation:

$A (x) = A_{in} +\frac{A_{out}-A_{in}}{L}\cdot x$

$\frac{A(x)}{A_{in}} = 1 + \left(\frac{1}{L}\right)\cdot \left( \frac{A_{out}}{A_{in}}-1\right)\cdot x$

After some algebraic manipulation, the following for the velocity as a function of position is obtained hereafter:

$\frac{v_{in}}{v(x)} = 1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}}-1\right) \cdot x$

$v(x) = \frac{v_{in}}{1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}}-1 \right)\cdot x}$

$v (x) = v_{in}\cdot \left[1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}}-1 \right)\cdot x \right]^{-1}$

The acceleration can be calculated by using the following derivative:

$a = v\cdot \frac{dv}{dx}$

The derivative of the velocity in terms of position is:

$\frac{dv}{dx} = -v_{in}\cdot \left(\frac{1}{L}\right) \cdot \left(\frac{v_{in}}{v_{out}}-1 \right) \cdot \left[1 + \left(\frac{1}{L}\right)\cdot \left(\frac{v_{in}}{v_{out}} -1 \right) \cdot x \right]^{-2}$

The expression for acceleration is derived by replacing each variable and simplifying the resultant formula.

8 0

3 years ago

Read 2 more answers

Define the isentropic efficiency for each of the following 3. a. i. Adiabatic turbine ii. Adiabatic compressor iii. Adiabatic no

Pavlova-9 [17]

Answer:

a) $\eta_{st}=\dfrac{\Delta h_{actual}}{\Delta _{ideal}}$

b) $\eta_{sc}=\dfrac{\Delta h_{ideal}}{\Delta _{actual}}$

c) $\eta_{sn}=\dfrac{\Delta h_{actual}}{\Delta _{ideal}}$

Explanation:

Adiabatic turbine

Adiabatic turbine means turbine can not reject or take heat from surrounding.

Isentropic efficiency of turbine can be define as the ratio of actual work out put to the Ideal or isentropic work out put.Ideal means when turbine will give maximum work and there is no any friction losses we can say when process is isentropic.

Isentropic efficiency of turbine=(Actual work output)/(Ideal work output)

$\eta_{st}=\dfrac{\Delta h_{actual}}{\Delta _{ideal}}$

Adiabatic compressor

Isentropic efficiency of compressor can be define as the ratio of ideal or isentropic work in put to the actual work in put.

Isentropic efficiency of turbine=(Ideal work input)/(actual work input)

$\eta_{sc}=\dfrac{\Delta h_{ideal}}{\Delta _{actual}}$

c)Adiabatic nozzle

We know that nozzle is device which used to accelerate the fluid.

Basically it covert pressure energy to kinetic energy.

Isentropic efficiency of nozzle can be define as the ratio of actual enthalpy drop put to the Ideal or isentropic enthalpy drop.

$\eta_{sn}=\dfrac{\Delta h_{actual}}{\Delta _{ideal}}$

3 0

4 years ago