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1. ### why we dont increase the PF(power factor to 1?we always keep it 0.85 is there any effect related to resonance?

I assume you're referring to power factor in the operation of power systems. In a power system the load is the customer and the power plant is the provider. The load (customer) usually demands power at a power factor of <1. This is...

2 Answers · Science & Mathematics · 25/11/2013

2. ### low power fm transmitter; with a 7 pf fixed disc capacitor instead of adjustable 3-18 pf, at what frequency wo?

In order to answer this question, we'll need a few more details. What type of oscillator is it? What is the value of the inductor in the tank circuit? What type of transistor is being used? What collector current is it...

2 Answers · Science & Mathematics · 11/11/2010

3. ### A 3500 pF capacitor is connected to a 55 mH coil of resistance 3ohms. What is the resonant frequency?

no, the resistance is not part of it. use f = 1/(2π√(LC)) .

1 Answers · Science & Mathematics · 03/12/2009

4. ### A 2800 pF air-gap capacitor is connected to a 22 V battery. If a piece of mica fills the space between the...?

Parallel plate cap C = ε₀εᵣ(A/d) in Farads ε₀ is 8.8542e-12 F/m εᵣ is dielectric constant (vacuum = 1) A and d are area of plate in m² and separation in m according to various...

1 Answers · Science & Mathematics · 20/07/2010

5. ### Do you think this capacitor is really rated for 15 kv 1000 pF?

It most likely is. 1000pF is VERY small (1,000,000,000,000pF = 1F), and generally, when dealing with a set size and type, the lower the capacitance the higher the voltage it can handle.

3 Answers · Science & Mathematics · 23/04/2013

6. ### A parallel-plate capacitor with air dielectric has a capacitance of 12 pF...?

a) times 5 b) x 4 x 5 c) x 2.2 x 6 x (1/2) Parallel plate cap C = ε₀εᵣ(A/d) in Farads ε₀ is vacuum permittivity, 8.854e-12 F/m εᵣ is dielectric constant or relative permittivity of the material (vacuum = 1...

3 Answers · Science & Mathematics · 04/08/2013

7. ### If P=1000W, pf=0.8 (leading), and Vrms=220V, what is the overall impedance?

VA = Power / Power Factor = 1000 / 0.8 = 1250 VA @ 36.87° Z = (V)(V*)/VA = ((220 @0°)(220@-0°))/1250 @ 36.87° = 38.72 Ohms at -36.87° Hope this helps.

2 Answers · Science & Mathematics · 07/12/2017

8. ### Upon what factors do the following quantities depend: Psc, Pf+w, Xm, X1 and Ior?

You have to define these terms, they could have dozens of different meanings.

1 Answers · Science & Mathematics · 26/10/2012

9. ### what resistive load and inductive load should i use in 1000va with .6 pf?

More info is needed. What voltage and frequency and what are you trying to do? Compensate a leading power factor to unity power factor?

1 Answers · Science & Mathematics · 25/01/2012

10. ### why it is not desirable to have a leading PF in electrical systems ?

Any power factor of < 1 (either leading or lagging) is undesireable because it represents volts and amps being used to transmit reactive power which causes losses and uses capacity in the system but...

1 Answers · Science & Mathematics · 31/03/2011