Download Radio Frequency - Robotics Academy

CAN I MAKE MY OWN SENSOR 1 Overview
In this lesson you will learn:
• How a potentiometer works as
a variable resistor and a
voltage divider
• How to use a multimeter as an
ohmmeter, voltmeter and
ammeter
• How to use Ohm’s Law
• How to predict values of
dependent variables
• How to calculate experimental
error
Vex 1.0 © 2005 Carnegie Mellon Robotics Academy Inc.
CAN I MAKE MY OWN SENSOR 1 Overview
In this investigation, you will learn how a potentiometer can be
used in an electronic circuit as a variable resistor or as a voltage
divider. Students will construct simple electronic circuits that use a
DC voltage source, a fixed value resistor and a rotary
potentiometer. This investigation consists of two activities.
Vex 1.0 © 2005 Carnegie Mellon Robotics Academy Inc.
CAN I MAKE MY OWN SENSOR 1 Lesson
Part 1: Potentiometer as Variable
Resistor
Set R(pot) to 1st value in Table 1-2
(125 Ohms)
Vex 1.0 © 2005 Carnegie Mellon Robotics Academy Inc.
CAN I MAKE MY OWN SENSOR 1 Lesson
Replace the potentiometer
back in circuit and measure
current (8.1 mA)
Vex 1.0 © 2005 Carnegie Mellon Robotics Academy Inc.
CAN I MAKE MY OWN SENSOR 1 Lesson
Part 2: Potentiometer as Voltage
Divider
Measure Component Values
Battery (unloaded)
Vex 1.0 © 2005 Carnegie Mellon Robotics Academy Inc.
CAN I MAKE MY OWN SENSOR 1 Lesson
Measure Component Values
(potentiometer’s maximum
resistance)
Vex 1.0 © 2005 Carnegie Mellon Robotics Academy Inc.
CAN I MAKE MY OWN SENSOR 1 Lesson
Connect Circuit (battery is
connected across the
potentiometer.)
Vex 1.0 © 2005 Carnegie Mellon Robotics Academy Inc.
CAN I MAKE MY OWN SENSOR 1 Lesson
Turn potentiometer dial to the
required output voltage reading. In
this case, Vout = 4.5 Volts)
Vex 1.0 © 2005 Carnegie Mellon Robotics Academy Inc.
CAN I MAKE MY OWN SENSOR 1 Lesson
Measure the potentiometer’s
resistance corresponding to R2
Vex 1.0 © 2005 Carnegie Mellon Robotics Academy Inc.