Select the correct answer.

What are the units or dimensions of the shear rate dv/dy (English units)? Then, what are the dimensions of the shear stress τ= μ

swat32

Answer:

1) Dimensions of shear rate is $[T^{-1}]$ .

2)Dimensions of shear stress are $[ML^{-1}T^{-2}]$

Explanation:

Since the dimensions of velocity 'v' are $[LT^{-1}]$ and the dimensions of distance 'y' are $[L]$ , thus the dimensions of $\frac{dv}{dy}$ become

$\frac{[LT^{-1}]}{[L]}=[T^{-1}]$ and hence the units become $s^{-1}$ .

Now we know that the dimensions of coefficient of dynamic viscosity $\mu$ are $[ML^{-1}T^{-1}]$ thus the dimensions of shear stress can be obtained from the given formula as

$[\tau ]=[ML^{-1}T^{-1}]\times [T^{-1}]\\\\[\tau ]=[ML^{-1}T^{-2}]$

Now we know that dimensions of momentum are $[MLT^{-1}]$

The dimensions of $Area\times time$ are $[L^{2}T]$

Thus the dimensions of $\frac{Moumentum}{Area\times time}=\frac{MLT^{-1}}{L^{2}T}=[MLT^{-2}]$

Which is same as that of shear stress. Hence proved.

4 0

2 years ago

Writing an excellent problem statement will not help guide you through the rest of the process and steer you towards the BEST so

Ilya [14]

Answer:

Writing an excellent problem statement will not help guide you through the rest of the process and steer you towards the BEST solution.

False

Explanation:

An excellent problem statement sets the overall tone for the rest of the engineering process, whether it be at the analysis, design, or implementation stages. This is why a problem statement must be focused, clear, and specific. An excellent problem statement contains the problem definition, method for solving the problem (the claim proposed), purpose, statement of objectives, and scope. For an excellent problem statement to be effective, it must also show the gap that is to be closed to achieve the intended objective.

4 0

2 years ago

A steel bar 110 mm long and having a square cross section 22 mm on an edge is pulled in tension with a load of 89,000 N, and exp

iragen [17]

Answer:

Elastic modulus of steel = 202.27 GPa

Explanation:

given data

long = 110 mm = 0.11 m

cross section 22 mm = 0.022 m

load = 89,000 N

elongation = 0.10 mm = 1 × $10^{-4}$ m

solution

we know that Elastic modulus is express as

Elastic modulus = $\frac{stress}{strain}$ ................1

here stress is

Stress = $\frac{Force}{area}$ .................2

Area = (0.022)²

and

Strain = $\frac{extension}{length}$ .............3

so here put value in equation 1 we get

Elastic modulus = $\frac{89,000\times 0.11}{0.022^2 \times 1 \times 10^{-4} }$

Elastic modulus of steel = 202.27 × $10^9$ Pa

Elastic modulus of steel = 202.27 GPa

3 0

2 years ago

Your study space does not need to be quiet as long as you can ignore any noise coming from the space true or false?

Makovka662 [10]

Answer:

False

Explanation:

When you're studying, you need to make sure that you can focus properly. This means that you shouldn't be hungry or too full and that you should be well-rested, in a quiet room with good lighting and no distractions. Noise is never good when you need to memorize something. Some people can partially ignore it as long as it isn't too loud, but it will begin to bother them eventually. That's why it's better to study in a quiet room.

3 0

2 years ago

Read 2 more answers

"Write a statement that outputs variable numItems. End with a newline. Program will be tested with different input values."

kirill [66]

Answer:

The solution code is written in Java.

System.out.println(numItems);

Explanation:

Java println() method can be used to display any string on the console terminal. We can use println() method to output the value held by variable numItems. The numItems is passed as the input parameter to println() and this will output the value of numItems to console terminal and at the same time the output with be ended with a newline automatically.

6 0

2 years ago