How Is Minimum Sensitivity Calculated in Instruments?

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Minimum sensitivity in instruments is defined as the change in output per unit change in the measured quantity. To calculate it, one participant initially plugged in the maximum input value of 5.0 mm into the sensitivity equation, yielding a voltage of 1.286 V, which they later deemed incorrect. They suggested that sensitivity should be determined by taking the derivative of the output with respect to the input, resulting in a value of -0.514 V/mm. The discussion emphasized that using a larger displacement like 5.0 mm provides a smaller rate of change, indicating lower sensitivity. The final consensus leaned towards using the absolute value for sensitivity, as negative values do not conceptually fit within the definition.
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Homework Statement
11kd1r5.jpg


The attempt at a solution
First, we define sensitivity as the change of an instrument or transducer's output per unit change in the measured quantity.

So to find the minimum sensitivity I simply plugged in the largest possible input (5.0 mm) into the equation:

E = 9.5e-0.4(5.0)

E = 1.286 V

Is this correct?
 
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I would say no, that is in fact the "minimum voltage" you would expect to occur

I would associate sensitivity with rate of change of voltage with distance
 


So I would first have to take the derivative, and then plug in 5.0?

Doing this I would get an answer of -0.514 V/mm. So will my final answer be 0.514 V/mm, if I were to take the absolute value?
 
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if you can explain why you choose 5 (which is a reasonable choice), it sounds like a plan
 


I chose a displacement of 5.0 mm because it will give me the smallest rate of change, whereas if I chose a number closer to 0, I would get a higher rate of change, which means higher sensitivity.

Also, do I keep the value negative, or take the absolute value? I don't think negative sensitivity makes sense.
 


may have to check you notes, it may be defined as the magnitude of rate of change as you're hinting
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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