Capacitance required to continue in a power lapse

In summary, a capacitor with a capacitance of C = Pt/ (1/2 V^2) would be required to protect a 150-watt television plugged into a standard 120-volt AC outlet from a 0.1-second lapse in power. This is because the energy released from a discharging capacitor is equal to the energy needed to tide the TV over the lapse time.
  • #1
Jacob87411
171
1
A capacitor is often used in electronics to keep energy flowing even if there is a momentary loss of power from the electric company. What capacitance would be required to a 150-watt televisiion (plugged into a standard 120 volt ac outlet) to protect it from a .1 second lapse in power?

I have done fine with every other question in this section but this one doesn't seem to be going as well. I am just curious how to begin. I know..

C=E0 x A/d (E0=permitivity of free space, 8.85x10^-12)
The time = .1 s

I just don't see how it all goes together
 
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  • #2
The energy released from a discharging capacitor that starts out with voltage V between its plates and continues to full discharge is given by : [tex]E = \frac{1}{2}CV^2[/tex]. This is the total energy released by the discharging capacitor. The energy needed to tide the TV over the lapse time is given by [tex]E = Pt[/tex] where P is the power and t is the time. Equate the two and figure out C.
 
  • #3
Thanks that makes a lot of sense
 

Related to Capacitance required to continue in a power lapse

1. What is capacitance and why is it important during a power lapse?

Capacitance is the ability of a system to store electrical charge. During a power lapse, capacitance is important because it helps to maintain a stable voltage and prevent sudden decreases in power.

2. How is the required capacitance determined during a power lapse?

The required capacitance during a power lapse is determined by the amount of power needed to keep essential systems running. This can be calculated by considering the voltage and current requirements of the systems and their expected duration of operation during the power lapse.

3. Can the required capacitance be too high or low during a power lapse?

Yes, the required capacitance can be too high or too low during a power lapse. If the capacitance is too high, it may lead to excessive energy consumption and potential damage to the systems. If it is too low, it may not provide enough power to maintain essential systems.

4. What are the consequences of not having enough capacitance during a power lapse?

Not having enough capacitance during a power lapse can result in sudden decreases in power, leading to potential damage to systems and disruptions in operations. It can also cause voltage fluctuations and instability, which can affect the performance of essential systems.

5. How often should the required capacitance be reassessed for a power lapse?

The required capacitance should be reassessed regularly, especially if there are changes in the systems or their power requirements. It is also important to test and maintain the capacitance to ensure it is functioning properly in case of a power lapse.

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