Exploring Simple Circuits: Components and Functions

The video tutorial explains the components and functions of four simple circuit diagrams. The first circuit investigates the potential difference across a lamp using a variable resistor. The second circuit is a light-detecting circuit with an LDR and LED. The third circuit is a temperature sensor using a thermostat and lamp. The fourth circuit demonstrates the action of a fuse with resistors in parallel. Each circuit's operation and purpose are detailed, highlighting the role of components like batteries, switches, and meters.

What is the purpose of the variable resistor in the first circuit?

• To keep the switch closed

• To measure the resistance of the lamp

• To change the current in the circuit

• To increase the voltage across the battery

In the light-detecting circuit, what happens when light is shone on the LDR?

• The resistance of the LDR increases

• The LED turns off

• The resistance of the LDR decreases

• The switch opens

How is the LED connected in the light-detecting circuit?

• With the arrow pointing from negative to positive

• With the arrow pointing from positive to negative

• In parallel with the LDR

• In series with the switch

What effect does heating the thermostat have in the temperature sensor circuit?

• It turns off the lamp

• It opens the switch

• It decreases the resistance

• It increases the resistance

What causes the fuse to blow in the fuse demonstration circuit?

• Decreasing the number of resistors in parallel

• Increasing the voltage of the battery

• Increasing the number of resistors in parallel

• Decreasing the current from the battery