List of top Biomedical Engineering Questions on Biomedical Sensors

A metallic strain gauge with negligible piezoresistive effect is subjected to a strain of \(50\times10^{-6}\). For the metal, Young’s Modulus \(=80\) GPa and Poisson’s ratio \(=0.42\). What is the change in resistance (in m\(\Omega\)), if the unstrained resistance is \(200~\Omega\)? (Round off the answer to one decimal place.)
A Wheatstone bridge strain gauge transducer is constructed on a diaphragm in such a way that when a force is applied on the diaphragm, the resistors \(R_1\) and \(R_4\) will be in compression, and the resistors \(R_2\) and \(R_3\) will be in tension. The bridge excitation voltage \((E_{\text{in}})\) is \(10\ \text{V}\). If all the resistors have a resistance of \(200\ \Omega\) in the absence of any force, and each resistance changes by \(20\ \Omega\) upon application of a force, what is the output voltage \(V_{\text{out}}\) (in Volts) from the Wheatstone bridge? (Round off your answer to the nearest integer.)
The resistance of a thermistor is 1 k\(\Omega\) at \(25^\circ\mathrm{C}\) and 500 \(\Omega\) at \(50^\circ\mathrm{C}\). Find the temperature coefficient of resistance (in units of \(^{\circ}\mathrm{C}^{-1}\)) at \(35^\circ\mathrm{C}\). (Round off the answer to three decimal places.)