1. ### Why this Simple Watt Meter for a 220 Volt Circuit works?

Hello guys! I'm just a begginer student. I found this circuit of a wattmeter that works only with resistors. Can someone explain to me how the 33k resistor give a voltage of 1 mV to 1 Watt? I did not understand why these resistor values has been chosen and why the it measures only in the 33k...
2. ### Camera which measures distance?

Hi all, I'm having trouble finding something online which isn't a very complicated device, but I don't know if it has a specific name, which would help me in a google search. I have a motor in an MBE which moves the sample, and I need a camera which can read to a computer what the distance is...
3. ### Problem measuring PH (it oscilates) for gastric juice

I bought a PH meter with glass electrode. I calibrated it using a buffer solution following the instructions. When I measure the PH of tap water, vinegar, or other simple liquids it initially keeps changing but eventually it stabilizes at the correct value. But I tried to measure gastric juice...
4. ### Electrical meter and efficiency question

Q1. I know a DMM will anticipate a sineusoidal supply, thus there can be problems with spiky supplies. Even if you have a true RMS meter, it it's a spikey supply, non-sineusoidal, you still can't calculate the peak of a spiky supply? Does a DMM measure the peak, then calculate from THAT the...
5. ### Converting ton to kN/m

Hello, can anyone help me to convert 180 ton to kN/m ? Which formula can you use to convert this? Thanks!