# voltage

1. ### Molecules With Radio Emission Under Current

I am working on a project, however I am having trouble finding the right material for it to work. I am looking for a nano-material or any molecule that will emit a radio frequency when subjected to a voltage or a current at around 37 degrees Celsius. I would really appreciate it if someone could...
2. ### Confusing relation between power,volatage and current

Hii,i'm new in electrical and much confused bcoz of complicated relation between V,I, nd P. If P = VI = cons. and increasing V,decrease the value of I, but since P is also equal to I×I ×R and r is cons.,so decrease in I will always cause P to decrease which is supposed to remain constant. And i...
3. ### DC power supply

How do i get 250v dc power supply?? Should I use lots of batteries or is there an easier way?
4. ### Lightbulb I/V curve question

The question I've been given this question by a teacher and I'm clueless as to what b) and c) are. Could you please help? I would really appreciate it. The prize is a place to see a lecture on quantum simulation at our local University. Thank you :)
5. ### Domestic Water Pump (1 HP)

Hi there, I have spent quite some time on PF as an unregistered user reading through various stuff and have learned a lot. Just registered now to seek help on something that's been bothering me a lot and to which I haven't managed to find a solution yet. Please let me know if this is not the...
6. ### Helmholtz Resonator using voltmeter

Hi, I am trying to understand how precisely a voltmeter is used to measure the resonant frequency of a sound wave in a helmholtz resonator. Is it simply that the maximum voltage corresponds to the resonant frequency? A detailed description or external link would be great. Many thanks.
7. ### Power dissipation limit for a resistor

I am confused about the concept of a power dissipation limit for a resistor. Basically for a resistor the product of the current through it and the potential across it should not exceed 0.25 watt otherwise it starts to heat up and act in a non-linear fashion. Is this value just a constant or is...
8. ### Finding Unknown Currents in a Two-battery Complex Circuit

1. Homework Statement Look at the circuit given in figure 1. Solve for the three currents, I1,I2,I3. 2. Homework Equations KVL: Sum of voltages in a closed loop equals zero KCL: Sum of currents entering a junction equals the sum of currents exiting a junction Ohm's Law: V=IR NOTE: Nodal...
9. ### Find the resistance for maximum power transfer

1. Homework Statement Find the value of R where RL equals 50 Ω, for maximum power transfer I= 2A, R_L=50 ohms 2. Homework Equations R_th=V_oc/I_sc KCL,KVL,V=IR 3. The Attempt at a Solution First, I created an open circuit including everything except R_L. Then i tried to solve for the Open...
10. ### Voltage transformers and magnetic field leakage

I’m looking to purchase a toroidal AUSTRALIA-to-US stepdown voltage transformer, and have narrowed my choice down to two models, one permitting a maximum rate of energy consumption of 100 Watts, and the other permitting a maximum rate of energy consumption of 250 Watts. Both of these maximum...