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

Semiconductor materials: cadmium sulphide, Energy gap: 2.4ev.   The...

Energy gap: 2.4ev.   The colour of pure cadmium sulphide is pale yellow. It melts only under at high temperature. It can be prepared in the resistivity range from 10 to

Has vc a limit, Has Vc a limit? Answer; precisely, but we do not know i...

Has Vc a limit? Answer; precisely, but we do not know its limit. But we know it is greater than c.

Quantum dots, can u tell me wats d QD which has excitation at in the 980nm ...

can u tell me wats d QD which has excitation at in the 980nm range?

How fast is the car moving at the top, A roller coaster starts from rest at...

A roller coaster starts from rest at the top of an 18m hill. The car travels to the bottom of the hill and continues up the next hill that is 10.0m high. How fast is the car moving

How much time is required to raise the temperature, how much time is requir...

how much time is required to raise the temperature of the water from A family comes home from a long vacation with laundry to-do and showers to take. The water heater has been t

Define force, Force: push or pull upon an object resulting from the object...

Force: push or pull upon an object resulting from the object's dealings with another object. Whenever there is an interaction among two objects, there is a force upon every of

What is the density of a cube, The density, ?, of an object is given by the...

The density, ?, of an object is given by the ratio of the object's mass, m, and volume, V, according to the equation ? = m/V. What is the density of a cube that is 1.2 cm on each s

Magnetic effects of current, a)  Explain the magnetic effects of current? ...

a)  Explain the magnetic effects of current? b)  Do the diagram to show the direction of motion of the conductor:

Polarisation, How can we ger plane polarised light??

How can we ger plane polarised light??

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