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In this section, you will multiply the data by the conversion scalar“k”that you found experimentally. You will also add an offset“b”.

1. Delete the Tone Measurement ExpressVI. Delete the Frequency and Amplitude indicators.

2. Delete the wires that connect the DAQ Assistant to the thermometer, the Waveform Graph, and the Write toFile ExpressVI. Press Ctrl+b to remove any broken wire remnants.

3. Place a Multiply and an Add on the block diagram.

4. Create a control and connect it to the y terminal of the Multiply icon. Rename the control“k”.

5. Create a control and connect it to the y terminal of the Add icon. Rename the control“b”.

6. Wire your block diagram as shown in Figure 4.

7. On the front panel, enter the values you found experimentally for the“k”and“b”values.

8. When you run the VI, your measurements should now be displayed as temperatures.

Part 3: time constants

The calibration curves you found represent static calibrations. In the following section, you will considerthe dynamic behavior of the sensors. The dynamics of all the temperature sensors used in this lab can be modeled accurately asfirst-order systems. The natural response of a first-order system can be characterized by a single parameter—the time constant.

Time constants can be found by observing the response of the instrument to a step input in temperature. Notethat the second medium governs the physics of the transient response. For each of the sensors, you will determine the timeconstant for transfers from ambient air to ice water and from hot air to ambient air.

An ice water bath will be provided for your tests. A heat gun will be used to generate hot air. Caution: Keepall temperature sensors (particularly the thermometer and the thermistor) at least 9 inches away from the heat gun. Holding themcloser to the heat gun will result in temperatures outside the operating range of the sensors.

Four methods will be used to calculate various time constants. Table 1 summarizes the tests to be performed. Thetesting methods are described below.

Table 1. Time constant calculation methods.

thermometer thermocouple thermistor
ambient air to ice water 1, 2 3, 4 3, 5
hot air to ambient air 1 3 3
ice water to ambient air - 3 -

Method 1- time elapsed at 63.2% sensor accuracy

Thermometer: Perform this test for ambient air to ice water. Repeat for hot air to ambient air.

1. Record the temperature of the initial medium, T0, and the temperature of the final medium, T_inf.

2. Calculate the intermediate reference temperature, Tr that is 63.2 percent of the way from T0 toT_inf.

3. With the instrument at steady state (reading T0) in the initial medium, move it quickly to the finalmedium.

4. The time from when the step in temperature began to when the instrument reads Tr is the time constant, . Thistime can be measured using a stopwatch.

Method 2 - mathematic definition of tau

Thermometer: Perform this test moving from ambient air to ice water.

1. Record the temperature of the initial medium, T0, and the temperature of the final medium, T_inf.

Questions & Answers

what is the coefficient of -4×
Mehri Reply
-1
Shedrak
the operation * is x * y =x + y/ 1+(x × y) show if the operation is commutative if x × y is not equal to -1
Alfred Reply
An investment account was opened with an initial deposit of $9,600 and earns 7.4% interest, compounded continuously. How much will the account be worth after 15 years?
Kala Reply
lim x to infinity e^1-e^-1/log(1+x)
given eccentricity and a point find the equiation
Moses Reply
12, 17, 22.... 25th term
Alexandra Reply
12, 17, 22.... 25th term
Akash
College algebra is really hard?
Shirleen Reply
Absolutely, for me. My problems with math started in First grade...involving a nun Sister Anastasia, bad vision, talking & getting expelled from Catholic school. When it comes to math I just can't focus and all I can hear is our family silverware banging and clanging on the pink Formica table.
Carole
I'm 13 and I understand it great
AJ
I am 1 year old but I can do it! 1+1=2 proof very hard for me though.
Atone
hi
Adu
Not really they are just easy concepts which can be understood if you have great basics. I am 14 I understood them easily.
Vedant
find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
I know this work
salma
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
Abhi
If f(x) = x-2 then, f(3) when 5f(x+1) 5((3-2)+1) 5(1+1) 5(2) 10
Augustine
how do they get the third part x = (32)5/4
kinnecy Reply
make 5/4 into a mixed number, make that a decimal, and then multiply 32 by the decimal 5/4 turns out to be
AJ
how
Sheref
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
hmm
Abhi
is it a question of log
Abhi
🤔.
Abhi
I rally confuse this number And equations too I need exactly help
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But this is not salma it's Faiza live in lousvile Ky I garbage this so I am going collage with JCTC that the of the collage thank you my friends
salma
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
hii
Uday
hi
salma
hi
Ayuba
Hello
opoku
hi
Ali
greetings from Iran
Ali
salut. from Algeria
Bach
hi
Nharnhar
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
Jeannette has $5 and $10 bills in her wallet. The number of fives is three more than six times the number of tens. Let t represent the number of tens. Write an expression for the number of fives.
August Reply
What is the expressiin for seven less than four times the number of nickels
Leonardo Reply
How do i figure this problem out.
how do you translate this in Algebraic Expressions
linda Reply
why surface tension is zero at critical temperature
Shanjida
I think if critical temperature denote high temperature then a liquid stats boils that time the water stats to evaporate so some moles of h2o to up and due to high temp the bonding break they have low density so it can be a reason
s.
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
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Source:  OpenStax, Introduction to mechanical measurements. OpenStax CNX. Oct 18, 2006 Download for free at http://cnx.org/content/col10385/1.1
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