Exploring Light Sensing with Circuit Playground Express

The video tutorial explains the function and applications of light sensors, particularly in the Circuit Playground Express. It covers the basics of conductors, insulators, and semiconductors, and delves into the workings of LEDs and depletion regions. The tutorial demonstrates how to build a simple tripwire system using a light sensor and flashlight, providing practical coding instructions. It concludes with potential real-world applications of light sensors, such as security systems and automatic lighting.

What is the primary function of a light sensor?

• To measure humidity

• To measure temperature

• To measure light intensity

• To measure sound levels

Where is the light sensor located on the Circuit Playground Express?

• Next to the A8 and I symbol

• Next to the B1 and J symbol

• Next to the C2 and K symbol

• Next to the D3 and L symbol

Which material allows electricity to flow through it?

• Insulator

• Conductor

• Semiconductor

• Capacitor

What is a semiconductor?

• A material that never allows electricity to flow

• A material that always allows electricity to flow

• A material that allows electricity to flow under special circumstances

• A material that stores electrical energy

What is the depletion region in a semiconductor?

• A region where positive and negative charges cancel each other out

• A region that always conducts electricity

• A region where only positive charges exist

• A region where only negative charges exist

What happens to the depletion region when light is shined onto an LED?

• It disappears

• It remains the same

• It becomes larger

• It becomes smaller

How does the capacitance of the PN junction change when light is removed?

• It remains constant

• It fluctuates randomly

• It increases

• It decreases

What is the purpose of setting the volume to over 200 in the tripwire system?

• To make the alarm quieter

• To make the alarm louder

• To turn off the alarm

• To change the pitch of the alarm

What should the light level block reading be to trigger the alarm in the tripwire system?

• Below 40

• Between 40 and 100

• Above 40

• Exactly 40

What kind of noise should the alarm make in the tripwire system?

• A low hum

• A screeching terrible noise

• A pleasing sound

• A musical tune