Measurement technology textbook problems

AI Thread Summary
The discussion covers various measurement technology problems, including the Wheatstone bridge circuit and its balance conditions, the Aron connection for three-phase power measurement, and the V-A method for resistance measurement. It emphasizes the importance of understanding the operating principles and relationships between mechanical and electrical parameters. The accuracy of different voltmeters for measuring DC voltage is also analyzed, with calculations suggested to determine the most precise instrument. Additionally, the impact of amplitude differences on waveform analysis is raised, highlighting the complexities in interpreting oscilloscope data. The conversation underscores the need for focused problem-solving in measurement technology.
NotFivehead
Messages
3
Reaction score
0
Homework Statement
Measurement technology problems
Relevant Equations
There is no single solution because there are multiple problems
1) Describe the Wheatstone bridge circuit and its condition for balance

2) What is shown in the figure? Explain its operating principle. Derive the relationship between the mechanical and electrical parameters.

3) We are measuring three-phase power using the Aron connection (2-wattmeter method). The power meter specifications are: I(n) = 3 A, U(n) = 300 V, cosφ(n) = 1, scale range = 150°, α₁ = 60°, α₂ = 72°, p(0) = 0,2.
a) What is the application condition for this connection method?
b) What is the active power consumption of the load?
c) What are the reactive and apparent power consumptions of the load?

4) We are measuring resistance using the V-A method. The voltmeter's measurement range is 50 V, and the ammeter's is 1,5 A. The measured voltage is 24 V, and the measured current is 0,8 A. The voltmeter's internal resistance is characterized by 2000 Ω/V, and the ammeter's internal resistance is 0,5 Ω. Both instruments have an accuracy class of 0,5.
a) Determine the measured value of the resistance!
b) Specify the circuit configuration that results in smaller systematic measurement error! Justify your choice! What causes this error?

5) We are measuring a DC voltage of U(measured) = 3 V using the following instruments:
- Deprez voltmeter, accuracy class h(accuracy class) = 0.5, measurement range U(measurement range) = 10 V
- Electrodynamic voltmeter, accuracy class h(accuracy class) = 1.5, measurement range U(measurement range) = 5 V
- 3½-digit digital voltmeter, error ±(0.2% FS + 2D), measurement range U(measurement range) = 20 V
Which instrument allows the most accurate measurement? Justify your choice with calculations!

6) The following waveform was observed on the oscilloscope screen:
a) What quantities can be measured based on the displayed waveform?
b) What is the phase difference between the two compared sinusoidal voltages?

My notes are in the PDF. I had to translate things from Hungarian, sorry in advance!
 

Attachments

Physics news on Phys.org
I think that you have received a DM by now from the Mentors mentioning that we usually prefer just one problem per thread. It is hard for most folks to respond to so many questions in one thread.

Having said that, I'll try to respond to one of the problems:
NotFivehead said:
Homework Statement: Measurement technology problems
Relevant Equations: There is no single solution because there are multiple problems

6) The following waveform was observed on the oscilloscope screen:
a) What quantities can be measured based on the displayed waveform?
b) What is the phase difference between the two compared sinusoidal voltages?
1750880236940.webp

The problem statement doesn't seem to say that the amplitudes of the two sinusoids are the same. What effect would different amplitudes have on the displayed figure?
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
Thread 'Correct statement about a reservoir with an outlet pipe'
The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
Thread 'A bead-mass oscillatory system problem'
I can't figure out how to find the velocity of the particle at 37 degrees. Basically the bead moves with velocity towards right let's call it v1. The particle moves with some velocity v2. In frame of the bead, the particle is performing circular motion. So v of particle wrt bead would be perpendicular to the string. But how would I find the velocity of particle in ground frame? I tried using vectors to figure it out and the angle is coming out to be extremely long. One equation is by work...
Back
Top