Explain how to calculate constant voltage source, Physics

Assignment Help:

Power is to be supplied from a source whose resistance is 20 K ? to a load of 100 ?. Would you consider it as a constant voltage source or current source? Explain.

Ans.

Given source is considered as a constant current source because, a source that has a very high internal resistance (20 K?) as compared to the load resistance (100 ?) is a constant current source.

Explanation: In figure below, a load impedance ZL is connected to a current source. Let It be the short-circuit current of source, and Zs be its internal impedance. Current IS is splitted into two parts IL through ZL and I1 through ZS. That is

 

1939_electronics.png

 

IS= I1+ IL

Or        I1= IS- IL

Because impedance Zs and  ZL are  in  parallel,  voltage  drop  across each must be equal, i.e.,

1145_equation.png

The above equation determines us that load current IL would remain almost the same as current IS, provided the ratio ZL/ZS= 100/20000 = 1/200 is small compared to unity. Source then behaves as a good current source.  Or we can say, the larger the value of internal impedance ZS (20K?) compared to load impedance ZL (100?), the smaller is the ratio ZL/ZS, and better it works as a constant current source.

 

 


Related Discussions:- Explain how to calculate constant voltage source

When a body is said to be in motion, MOTION: A body is said to be in ...

MOTION: A body is said to be in motion if it alters its position with respect to its surroundings.

What mass of coal can the barge carry in freshwater, An open barge has the ...

An open barge has the dimensions 22x40x12m. If the bargeis made out of 4.0-cm-thick steel plate on each of its four sides and its bottom, what mass of coal can the barge carry in f

Determine the mass spectrograph, In the mass spectrograph, two positively c...

In the mass spectrograph, two positively charged ions having the similar velocity pass through a slit and enter a uniform magnetic field at right angles to their initial velocities

Ac input resistance in common emitter configuration, AC Input Resistance in...

AC Input Resistance in Common Emitter Configuration Ratio of change in base emitter  voltage  ( ? V BE )  to  the  resulting  change  in  base  current  ( ? I B )  at  cons

Explain the diagramming waves, Explain the Diagramming Waves? There are...

Explain the Diagramming Waves? There are two ways that waves can be indicated in a two-dimensional diagram. Parallel lines can be drawn that are meant to show the position of

Thermal equillibrium, a column of water contains fine metal particles of ra...

a column of water contains fine metal particles of radius 2*E(-8) m, which are in thermal equillibrium at 298 K. if there are 1000 particles per unit volume at a given height,how m

Quantum, What is the mass ms of one 294Uus atom, in SI units? Include the e...

What is the mass ms of one 294Uus atom, in SI units? Include the error bars in your answer, using 1 atomic mass unit 1u = (1.66053892 ± 0.00000007) × 10-27 kg.

Simple harmonic motion, what is the displacement of the body when potential...

what is the displacement of the body when potential and kinetic energies are eqal?

Magnifying glass, Magnifying Glass: A biconvex lens of short focal leng...

Magnifying Glass: A biconvex lens of short focal length and low power which forms a virtual and magnified image of an object placed with its focal length is known as magnifying

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd