The image above represents the apparent shear stress | slit die.

To compute for apparent shear stress | slit die, three essential parameters are needed and these parameters are **height of die (h), pressure gradient (ΔP)** and** flow length (L).**

The formula for calculating the apparent shear stress | slit die:

τ_{app} = ^{h . ΔP} / _{2L}

Where:

τ_{app} = Apparent Shear Stress | Slit Die

h = Height of Die

ΔP = Pressure Gradient

L = Flow Length

Let’s solve an example;

Find the apparent shear stress | slit die when the height of die is 7, pressure gradient is 12 and the flow length is 16.

This implies that;

h = Height of Die = 7

ΔP = Pressure Gradient = 12

L = Flow Length = 16

τ_{app} = ^{h . ΔP} / _{2L}

τ_{app} = ^{7 . (12)} / _{2(16)}

τ_{app} = ^{84} / _{32}

τ_{app} = 2.625

Therefore, the **apparent shear stress** is **2.625.**

**Calculating the Height of Die when the Apparent Shear Stress, Pressure Gradient and the Flow Length is Given.**

h = ^{τapp x 2L} / _{ΔP}

Where:

h = Height of Die

τ_{app} = Apparent Shear Stress | Slit Die

ΔP = Pressure Gradient

L = Flow Length

Let’s solve an example;

Find the height of die when the apparent shear stress | slit die is 32, the pressure gradient is 10 and the flow length is 8.

This implies that;

τ_{app} = Apparent Shear Stress | Slit Die = 32

ΔP = Pressure Gradient = 10

L = Flow Length = 8

h = ^{τapp x 2L} / _{ΔP}

h = ^{32 x 2 (8)} / _{10}

h = ^{32 x 16} / _{10}

h = ^{512} / _{10}

h = 51.2

Therefore, the **height of die **is **51.2.**

**Calculating the Pressure Gradient when the Apparent Shear Stress, Height of Die and the Flow of Length is Given.**

ΔP = ^{τapp x 2L} / _{h}

Where:

ΔP = Pressure Gradient

τ_{app} = Apparent Shear Stress | Slit Die

h = Height of Die

L = Flow Length

Let’s solve an example;

Find the pressure gradient when the apparent shear stress | slit die is 16, the height of die is 4 and the flow length is 2.

This implies that;

τ_{app} = Apparent Shear Stress | Slit Die = 16

h = Height of Die = 4

L = Flow Length = 2

ΔP = ^{τapp x 2L} / _{h}

ΔP = ^{16 x 2 (2)} / _{4}

ΔP = ^{16 x 4} / _{4}

ΔP = ^{64} / _{4}

ΔP = 16

Therefore, the **pressure gradient **is **16.**

**Calculating the Flow Length when the Apparent Shear Stress when the Height of Die and the Pressure Gradient is Given.**

L = ^{h . ΔP} / _{τapp x 2}

Where:

L = Flow Length

τ_{app} = Apparent Shear Stress | Slit Die

h = Height of Die

ΔP = Pressure Gradient

Let’s solve an example;

Find the flow length when the apparent shear stress | slit die is 15, the height of die is 10 and the pressure gradient is 4.

This implies that;

τ_{app} = Apparent Shear Stress | Slit Die = 15

h = Height of Die = 10

ΔP = Pressure Gradient = 4

L = ^{h . ΔP} / _{τapp x 2}

L = ^{10 . 4} / _{15 x 2}

L = ^{40} / _{30}

L = 1.33

Therefore, the **flow length **is **1.33.**

Nickzom Calculator – **The Calculator Encyclopedia** is capable of calculating the apparent shear stress | slit die.

To get the answer and workings of the apparent shear stress | slit die using the **Nickzom Calculator – The Calculator Encyclopedia. **First, you need to obtain the app.

You can get this app via any of these means:

**Web** – https://www.nickzom.org/calculator-plus

To get access to the **professional **version via web, you need to **register** and **subscribe **for** NGN 1,500 **per** annum** to have utter access to all functionalities.

You can also try the **demo **version via https://www.nickzom.org/calculator

**Android (Paid)** – https://play.google.com/store/apps/details?id=org.nickzom.nickzomcalculator

**Android (Free)** – https://play.google.com/store/apps/details?id=com.nickzom.nickzomcalculator

**Apple (Paid)** – https://itunes.apple.com/us/app/nickzom-calculator/id1331162702?mt=8

Once, you have obtained the calculator encyclopedia app, proceed to the **Calculator Map, **then click on **Polymer & Textile**** **under **Engineering****.**

Now, Click on **Appa****rent Shear Stress| Slit Die**** **under **Polymer & Textile**

The screenshot below displays the page or activity to enter your values, to get the answer for the apparent shear stress | slit die according to the respective parameters which is the **height of die (h), pressure gradient (ΔP)** and** flow length (L).**

Now, enter the values appropriately and accordingly for the parameters as required by the **height of die (h)** is **7**,** pressure gradient (ΔP)** is **12 **and** flow length (L)** is **16**.

Finally, Click on Calculate

As you can see from the screenshot above, **Nickzom Calculator**– The Calculator Encyclopedia solves for the apparent shear stress | slit die and presents the formula, workings and steps too.