Your house Flashcards
what are incandescent lightbulbs?
These contain a filament that get so hot they give out visible light.
Are incandescent light bulbs energy efficient?
No because they mainly heat the room and not light it up.
the calculation:
useful energy(or power) out X100
________
total energy(or power) in
efficiency (%)
What does LED stand or?and why do we use them?
It stands for light-emitting diode. It is a light bulb that is more efficient.
What does LDR stand for and what is it?
It stands for Light-dependent resistor and it is a sensor.
True or false:
An LDR’s resistance changes in different light levels.
True
If the light levels are high. What is the resistance of the LDR?
It is low
You would need an LDR outside and inside a room for it to detect whether to switch the lights on or not. Why is this?
This because you create a sensing circuit so the LDR can sense if the ligh is on or off in the room and whether it is day or night outside.
You may even be able to control a sensing circuit from our ________.
Phone
