Power Laws and Log-log Plots Slope = n Intercept = log k Incroprera, Fundamentals of Heat Transfer, 6th edition (2006). General Linearization transformation Use linear curve fit to get a and b, which can be used to extrapolate physical parameters.

RTD – Resistance Temperature Detector The resistivity of a metal changes linearly with temperature. Lab1: Voltage divider circuit

Thermistor Steinhart Eq. Works the same as an RTD, except the sensing material is made of a ceramic or a semiconductor. Steinhart Eq. Lab 1 Non-linear response

Voltage Divider Circuit

Often wired up in a Wheatsone bridge configurartion Strain Gauge (or Gage) Measures strain based on change in resistance Ge ≈ 2 “gage factor” Fig. 4.4 Often wired up in a Wheatsone bridge configurartion

Wheatstone Bridge

Micro-Electro-Mechanical Systems (MEMS) Modern Accelerometers Acceleration causes mass to push on spring and displace the “interdigitated” electrodes, changes electric capacitance. Micro-Electro-Mechanical Systems (MEMS) 3-axis gyro from an iPhone 4

In E1a, you will use this 3-axis accelerometer Lab1 Accelerometer Calibration In E1a, you will use this 3-axis accelerometer