## How to Calculate and Solve for Resistance Change of Thermistor as a First Order Approximation | Temperature Measuring Instruments 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 (To).

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

ΔR = k(T – To)

Where:

ΔR = Resistance Change in Thermistor as a First Order Approximation
K = Value
T = Temperature of Thermistor
To = 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
To = Ambient Temperature = 11

ΔR = k(T – To)
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
To = 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
To = Ambient Temperature = 14

K = ΔR / (T – To)
K = 22 / (18 – 14)
K = 22 / 4
K = 5.5

Therefore, the value is 5.5.

## How to Calculate and Solve for Green Ampt Infiltration Model | Methods of Application of Water The image above represents green ampt infiltration model.

To compute for green ampt infiltration model, three essential parameters are needed and these parameters are Value (Ks), Distance from the Ground Surface to the Wetting Front (L) and Capillary Suction at the Wetting Front (S).

The formula for calculating green ampt infiltration model:

Fp = Ks(L + S) / L

Where:

Fp = Green Ampt Infiltration Model
Ks = Value
L = Distance from the Ground Surface to the Wetting Front
S = Capillary Suction at the Wetting Front

Let’s solve an example;
Find the green ampt infiltration model when the value is 21, the distance from the ground surface to the wetting front is 15 and capillary suction at the wetting front is 4.

This implies that;

Ks = Value = 21
L = Distance from the Ground Surface to the Wetting Front = 15
S = Capillary Suction at the Wetting Front = 4

Fp = Ks(L + S) / L
Fp = 21(15 + 4) / 15
Fp = 21(19) / 15
Fp = 399 / 15
Fp = 26.6

Therefore, the green ampt infiltration model is 26.6.

## How to Calculate and Solve for Discharge of a Ventruiflume | Methods of Application of Water The image above represents discharge of a ventruiflume.

To compute for discharge of a ventruiflume, seven essential parameters are needed and these parameters are Value (Ca), an, Value (g), Water depth (h1), Water depth (h2), Cross-section area at inlet (a1) and Cross-section area at throat portion (a2).

The formula for calculating discharge of a ventruiflume:

Q = Caan√(2g(h1 – h2)) / a1² – a2²

Where:

Q = Discharge of a Ventruiflume
Ca = Value
an = an
g = Value
h1 = Water Depth
h2 = Water Depth
a1 = Cross-Section Area at Inlet
a2 = Cross-Section Area at Throat Portion

Let’s solve an example;
Find the discharge of a ventruiflume when the value is 2, an is 4, value is 7, water depth is 11, water depth is 10, cross-section area at inlet is 12 and cross-section area at throat portion is 5.

This implies that;

Ca = Value = 2
an = an = 4
g = Value = 7
h1 = Water Depth = 11
h2 = Water Depth = 10
a1 = Cross-Section Area at Inlet = 12
a2 = Cross-Section Area at Throat Portion = 5

Q = Caan√(2g(h1 – h2)) / a1² – a2²
Q = 2(4)√(2(7)(11 – 10)) / (12)² – (5)²
Q = 2(4)√(2(7)(1)) / (144) – (25)
Q = 2(4)√(14) / 119
Q = 2(4)(3.741) / 119
Q = 29.93 / 119
Q = 0.25

Therefore, the discharge of a ventruiflume is 0.25.

## How to Calculate and Solve for Standard Normal Variable | Probability The image above represents standard normal variable.

To compute for standard normal variable, three essential parameters are needed and these parameters are value (x), mean (μ) and standard deviation (σ).

The formula for calculating standard normal variable:

z = (x – μ)σ

Where;

z = Standard Normal Variable
x = Value
μ = Mean
σ = Standard Deviation

Let’s solve an example;
Find the standard normal variable when the value is 4, the mean is 20 and the standard deviation is 26.

This implies that;

x = Value = 4
μ = Mean = 20
σ = Standard Deviation = 26

z = (x – μ)σ
z = (4 – 20)26
z = (-16)26
z = -0.615

Therefore, the standard normal variable is -0.615.