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

Motion, a car of mass 800kg is pulling a trailer 300kg where sin a=1|200.R...

a car of mass 800kg is pulling a trailer 300kg where sin a=1|200.Resistance to motion(apart from gravity) is 1.5N per kg of mad for each vehicle.calculate the pulls of the engine

What is the magnitude of the magnetic induction, The magnetic vector potent...

The magnetic vector potential in a specific region is a constant vector having magnitude 4πX10 5 units and points along the positive x-axis. What is the magnitude of the magnetic

What is asteroids, What is an asteroid, comet, dwarf planet with respect to...

What is an asteroid, comet, dwarf planet with respect to their mass, moment of inertia and dimension? Ans) Dwarf Planet is lighter,smaller than a planet ( Pluto ).They usually a

Evaluate diameters of bright and dark newtons rings, Q. Evaluate Diameters ...

Q. Evaluate Diameters of Bright and Dark Newtons Rings? Let ‘R' is the radius of curvature of a Plano-convex lens resting at a glass plate PQ. If t be the thickness of air film

Reducing friction with ball bearings, Reducing friction with ball bearings ...

Reducing friction with ball bearings  Find two tin cans that have a deep groove approximately the top, such as paint cans. Lay marbles in single groove and invert the other can

Resistors in parallel , Resistor in Parallel  Components are said to be ...

Resistor in Parallel  Components are said to be in parallel when they are connected in such a way as to provide alternative paths for current flow. The characteristics o

Newtons laws of motion, Newton's laws of motion (Sir I. Newton) Newto...

Newton's laws of motion (Sir I. Newton) Newton's first law of motion A body remain continues in its state of constant velocity (that may be zero) unless it is acted on

Who shared the nobel prize in 1909 with guglielmo marconi, Who shared the N...

Who shared the Nobel Prize in Physics in 1909 with Guglielmo Marconi for his contribution to the development of wireless telegraphy? Ans: (Carl Ferdinand) Braun shared the N

Force, what is turning force and moment force ?

what is turning force and moment force ?

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