The image above represents resistance change of thermistor as a first order approximation.

To compute for resistance change of thermistor as a first order approximation, three essential parameters are needed and these parameters are **Value (K), Temperature of Thermistor (T) **and **Ambient Temperature (T _{o}).**

The formula for calculating resistance change of thermistor as a first order approximation:

ΔR = k(T – T_{o})

Where:

ΔR = Resistance Change in Thermistor as a First Order Approximation

K = Value

T = Temperature of Thermistor

T_{o} = Ambient Temperature

Let’s solve an example;

Find the resistance change in thermistor as a first order approximation when the value is 22, the temperature of thermistor is 16 and the ambient temperature is 11.

This implies that;

K = Value = 22

T = Temperature of Thermistor = 16

T_{o} = Ambient Temperature = 11

ΔR = k(T – T_{o})

ΔR = 22 x (16 – 11)

ΔR = 22 x 5

ΔR = 110

Therefore, the **resistance change of thermistor as a first order approximation **is **110 Ω.**

**Calculating for the Value when the Resistance Change of Thermistor as a First Order Approximation, the Temperature of Thermistor and the Ambient Temperature is Given.**

K = ^{ΔR} / _{(T – To)}

Where;

K = Value

ΔR = Resistance Change in Thermistor as a First Order Approximation

T = Temperature of Thermistor

T_{o} = Ambient Temperature

Let’s solve an example;

Find the value when the resistance change in thermistor as a first order approximation is 22, the temperature of thermistor is 18 and the ambient temperature is 14.

This implies that;

ΔR = Resistance Change in Thermistor as a First Order Approximation = 22

T = Temperature of Thermistor = 18

T_{o} = Ambient Temperature = 14

K = ^{ΔR} / _{(T – To)}

K = ^{22} / _{(18 – 14)}

K = ^{22} / _{4}

K = 5.5

Therefore, the **value **is **5.5.**

**Calculating for Temperature of Thermistor when the Resistance Change of Thermistor as a First Order Approximation, the Value and the Ambient Temperature is Given.**

T = (^{ΔR} / _{K}) + T_{o}

Where;

T = Temperature of Thermistor

ΔR = Resistance Change in Thermistor as a First Order Approximation

K = Value

T_{o} = Ambient Temperature

Let’s solve an example;

Find the temperature of thermistor when the resistance change in thermistor as a first order approximation is 10, the value is 4 and the ambient temperature is 8.

This implies that;

ΔR = Resistance Change in Thermistor as a First Order Approximation = 10

K = Value = 4

T_{o} = Ambient Temperature = 8

T = (^{ΔR} / _{K}) + T_{o}

T = (^{10} / _{4}) + 8

T = 2.5 + 8

T = 10.5

Therefore, the **temperature of thermistor **is **10.5.**

**Calculating for Ambient Temperature when the Resistance Change of Thermistor as a First Order Approximation, the Value and the Temperature of Thermistor is Given.**

T_{o} = (^{ΔR} / _{K}) + T

Where;

T_{o} = Ambient Temperature

ΔR = Resistance Change in Thermistor as a First Order Approximation

K = Value

T = Temperature of Thermistor

Let’s solve an example;

Find the ambient temperature when the resistance change in thermistor as a first order approximation is 18, the value is 10 and the temperature of thermistor is 6.

This implies that;

ΔR = Resistance Change in Thermistor as a First Order Approximation = 18

K = Value = 10

T = Temperature of Thermistor = 6

T_{o} = (^{ΔR} / _{K}) + T

T_{o} = (^{18} / _{10}) + 6

T_{o} = 1.8 + 6

T_{o} = 7.8

Therefore, the **ambient temperature **is **7.8.**

Nickzom Calculator – **The Calculator Encyclopedia** is capable of calculating the resistance change of thermistor as a first order approximation.

To get the answer and workings of the resistance change of thermistor as a first order approximation using the **Nickzom Calculator – The Calculator Encyclopedia. **First, you need to obtain the app.

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Once, you have obtained the calculator encyclopedia app, proceed to the **Calculator Map, **then click on **Materials and Metallurgical **under **Engineering****.**

Now, Click on **instrumentation **under **Materials and Metallurgical**

Now, Click on **Temperature Measuring Instruments** under **Instrumentation**

Now, Click on **Resistance Change of Thermistor as a First Order Approximation**** **under **Temperature of Measuring Instruments**

The screenshot below displays the page or activity to enter your values, to get the answer for the resistance change of thermistor as a first order approximation according to the respective parameters which is the **Value (K), Temperature of Thermistor (T) **and **Ambient Temperature (T _{o}).**

Now, enter the values appropriately and accordingly for the parameters as required by the **Value (K), Temperature of Thermistor (T) **and **Ambient Temperature (T _{o}).**

Finally, Click on Calculate

As you can see from the screenshot above, **Nickzom Calculator**– The Calculator Encyclopedia solves for the resistance change of thermistor as a first order approximation and presents the formula, workings and steps too.