A very quick query about strain gauges

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In summary, A project is being done on strain gauges using a half-wheatstone bridge setup. The goal is to measure weight by attaching strain gauges to a ruler/cantilever and bending it with weight. The reading on the bridge should be zero when the gauges are unstrained. The voltage difference is being measured, not current. The resistance difference across the bridge will be recorded as a voltage change when the gauges are bent. A question is posed about whether the voltage reading on the scales will increase with more bending. The person speaking apologizes for any confusion and asks what voltage is being measured. They also suggest using a spell checker for clearer communication.
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I am doing a project on strain gauges. I have the thing set up in a half-wheatstone bridge. Using a pair of strain gauges I am trying to measure the weight!(attaching each one to a side of a ruler/cantilever and bending it by attaching weight to the end)

So here's a confusing bit. I no when the gauges are unstrained the reading on the bridge shud be ZERO(i.e bridge is balanced) I'm measuring the voltage difference across the bridge not current. The point is when i bend them i get a reading(which i shud)

Am i correct in assuming that the resistance difference across the bridge when i bend it. This will b recorded as a voltage change?
SO here's a question. If i bend it more the resistance difference should b greater so should i get a bigger reading (voltmeter) on the scales or not??

I no the explanation isn't a perfect . PLease bear with me.
 
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What voltage are you measuring?

If I recall correctly a Wheatstone bridge relies on current measurements. If one arm is out of balance, a current will flow through the center, you then adjust the resistance in the arm opposite the load to zero the current.

You may want to check into a spell checker, while it is possible to figure out what you are trying to say, frequently I will simply go to the next message rather then attempt to figure out something as poorly written as your message.
 
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Yes, you are correct in assuming that the resistance difference across the bridge will be recorded as a voltage change when you bend the strain gauges. As you bend the ruler/cantilever more, the resistance difference will be greater and therefore the voltage reading on the scales should be bigger. This is because the strain gauges are converting the mechanical strain into an electrical signal, which is then measured as a change in voltage. So the more the ruler/cantilever is bent, the greater the change in resistance and thus the greater the change in voltage. I hope this helps clarify things for you. Good luck with your project!
 

1. What is a strain gauge?

A strain gauge is a device used to measure the strain or deformation of an object. It works by converting mechanical strain into a change in electrical resistance, which can then be measured and recorded.

2. How does a strain gauge work?

A strain gauge typically consists of a thin wire or foil that is attached to the surface of the object being measured. As the object deforms, the wire or foil also stretches or compresses, causing a change in its electrical resistance. This change in resistance is then measured and used to calculate the strain of the object.

3. What are the applications of strain gauges?

Strain gauges are commonly used in engineering and scientific fields to measure the strain of various materials and structures. They are used in the development of new products, testing the durability of materials, and monitoring the structural health of buildings and bridges.

4. Are there different types of strain gauges?

Yes, there are several types of strain gauges, including foil strain gauges, semiconductor strain gauges, and bonded wire strain gauges. Each type has its own advantages and is suitable for different applications.

5. How accurate are strain gauges?

The accuracy of a strain gauge depends on various factors, such as the quality of the gauge, the calibration process, and the conditions in which it is used. Generally, strain gauges have a high accuracy and can measure strain within a range of 0.1% to 0.001% of the original length of the object being measured.

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