Hello, I enjoy your video presentations. Thank you. I have a question. What hand held point and observe apparatus would I use to find the Kelvin temperature of white light?
If you use water as an analogy for electricity, voltage is like water pressure and current is like the water flow. Watts are a unit of power which are calculated by multiplying voltage and current. It’s hard to explain but the beginning of this video explains it well. ua-cam.com/video/mvuHsu8S6v8/v-deo.html
So, I want to make me a 144 Led Unit/m, 120cm TL tube, which gives light (Lumen) as much as an old 150w Osram spotlightbulb. What specification do the LEDs need to be, knowing there be around 170 LED units in 120cm, what power source will I need? Thank you.
if you use an LED strip, it will pull c.15W/m if you take something good and bright. The best led strips output 160-180lm/m, it's common for good ones to output c.120lm. LED strips can run on 5v, 12, 24, 120 or 220v, so you need to choose the power supply accordingly. for 1.2 meters or led strips, you would need under 20W, so if you take a 30W PSU, you're fine. If you happen to use 24V strips, for eg, you could use a 24V 1.5A PSU. Watts = V x A
It can on a dimming circuit - dimmers usually specify a minimum wattage as below that they won’t recognise the load and the lights won’t work. It should be fine on a switched circuit.
Dear Eleanor You are simply the best on youtube by miles! You certainly know your stuff and brilliant teacher 👌
Thank you! 😃
every days a school day! Thanks for explaining things so well!
You're so welcome!
Thank you Eleanor! A simple explanation at last.
Great! Gald it helped!
❤thanks
THANK YOU for this. I want to support all the brilliant women out there and not jut listen to men explain things to me . . .
Thanks!
Hello,
I enjoy your video presentations. Thank you.
I have a question. What hand held point and observe apparatus would I use to find the Kelvin temperature of white light?
What is Volt? And what is the difference between volt and watt?
If you use water as an analogy for electricity, voltage is like water pressure and current is like the water flow. Watts are a unit of power which are calculated by multiplying voltage and current. It’s hard to explain but the beginning of this video explains it well.
ua-cam.com/video/mvuHsu8S6v8/v-deo.html
So, I want to make me a 144 Led Unit/m, 120cm TL tube, which gives light (Lumen) as much as an old 150w Osram spotlightbulb.
What specification do the LEDs need to be, knowing there be around 170 LED units in 120cm, what power source will I need?
Thank you.
if you use an LED strip, it will pull c.15W/m if you take something good and bright. The best led strips output 160-180lm/m, it's common for good ones to output c.120lm. LED strips can run on 5v, 12, 24, 120 or 220v, so you need to choose the power supply accordingly. for 1.2 meters or led strips, you would need under 20W, so if you take a 30W PSU, you're fine. If you happen to use 24V strips, for eg, you could use a 24V 1.5A PSU. Watts = V x A
I know putting a higher watt lightbulb can distroy a circuit but can too little wattage be a problem?
It can on a dimming circuit - dimmers usually specify a minimum wattage as below that they won’t recognise the load and the lights won’t work. It should be fine on a switched circuit.
It’s a bit like horse power. We don’t use horses anymore.