• 🤓 What are they?
  LDRs are like the photogenic siblings of thermistors! They're made from semiconductor materials, just like thermistors. But here's the twist - LDRs are all about the limelight, literally. They respond to light, not temperature.

• 💡 How do they work?
  Imagine you’re sunbathing. The sun's rays hit you, and you feel warm, right? Well, for LDRs, when photons (those are light particles) hit them, they get excited and release electrons. The more the light, the more electrons are set free. This is kinda like how thermistors release electrons with heat.

• 🎢 Rollercoaster of Resistance:
  More light = less resistance in LDRs. So, it's inverse! Imagine a seesaw; when light goes up, resistance goes down.

  Real-world example: Imagine a night light that becomes brighter as the room gets darker. That’s an LDR in action! When the room is dark, the LDR has high resistance, allowing more current to flow and making the bulb brighter.

• Let's Set The Stage: We're going to play detective with metal wires! Investigating how resistance changes with their size and shape. It's kinda like seeing how a straw's resistance to your drink changes based on its length and width!🥤

• Tools & Toys

  • Wires (all from the same metal or metal alloy). Picture them as different-sized straws!
  • A method to vary one wire’s length. Imagine stretching or compressing that straw.
  • A circuit (use the design from Figure 14, though sadly not provided here).

• Questions to Crack

• How does the resistance (R) change when we play with a wire’s length (l)?
  • Hint: Try doubling or halving the length and see what happens. It's like checking if a longer or shorter straw makes it harder or easier to drink!
• How about when we mess with the diameter (d) of wires of the same length?
  • Hint: Plotting a graph of resistance against diameter might spill the beans.

Real-world example: Think of a garden hose. A shorter hose lets the water out faster, while a longer one makes it harder (higher resistance). And a wider hose (larger diameter) lets out more water than a skinny one.