Week 9 Quiz: Basic Sensors and Input Devices

Question 1: Sensor Types

What is the main difference between digital and analog sensors?

A) Digital sensors are more expensive than analog sensors B) Digital sensors output HIGH/LOW signals, analog sensors output variable voltages C) Digital sensors work faster than analog sensors D) There is no difference between them

Question 2: Pull-up Resistors

Why do we use INPUT_PULLUP when reading button states?

A) To make the button press faster B) To ensure the pin reads a defined state when button is not pressed C) To increase the button's voltage D) To protect the Arduino from damage

Question 3: Button Debouncing

What problem does button debouncing solve?

A) It makes buttons last longer B) It prevents multiple rapid signals from mechanical switch bounce C) It increases button sensitivity D) It reduces power consumption

Question 4: Potentiometer Range

What range of values does analogRead() return when reading a potentiometer?

A) 0 to 255 B) 0 to 1023 C) 0 to 5 D) 0 to 100

Question 5: Sensor Applications

Which sensor would be best for detecting motion in a security system?

A) Temperature sensor B) Light sensor (LDR) C) PIR (Passive Infrared) sensor D) Potentiometer

Question 6: Signal Filtering

What is the purpose of applying a moving average filter to sensor readings?

A) To make readings faster B) To smooth out noise and create more stable readings C) To increase sensor accuracy D) To reduce power consumption

Question 7: Analog Pin Usage

How many analog input pins does Arduino Uno have?

A) 4 pins (A0-A3) B) 6 pins (A0-A5) C) 8 pins (A0-A7) D) 14 pins (same as digital)

Question 8: Map Function

What does the map() function do when working with sensor values?

A) It stores sensor values in memory B) It converts values from one range to another range C) It displays sensor values on a screen D) It filters out noise from sensors

Question 9: Sensor Selection

You're building an automatic plant watering system. Describe what types of sensors you would use and explain how each sensor would contribute to the system's functionality.

Question 10: Troubleshooting

A student reports that their button sometimes registers multiple presses when they only pressed it once, and sometimes doesn't register a press at all. What are two likely causes of this problem and how would you fix each one?