Calculating unknown resistances by wheatstone bidge, Physics

Assignment Help:

Calculating unknown resistances

The current through the galvanometer (G) - a very sensitive ammeter, is reduced to zero by adjusting R4.  The bridge is then said to be balanced.  When the bridge is balanced, the voltage at A is equal to the voltage at B and no current flows between A and B.

424_wheat stone bridge.png

 

Hence       VR1             =       VR2

          therefore   I1 ´ R1           =       I2 ´ R2 ------------- (1)  (by Ohm's law)

          Also           VR3             =       VR4

          therefore   I1 ´ R3        =       I2 ´ R4 ------------- (2)

 

 

Dividing (1) by (2) 1368_Calculating unknown resistances.png

 

Therefore the unknown resistor  R3  = 1887_Calculating unknown resistances1.png    (all known values)

In calculations it is possible for any of the four resistors to be unknown.  However, provided that the bridge is balanced, the theory remains the same and all that is required is to transpose the equation to find the unknown 

 


Related Discussions:- Calculating unknown resistances by wheatstone bidge

What is the magnitude of the northward acceleration, A man exerts a northwa...

A man exerts a northward force of 100 newtons on a 50 kilogram box which sits on a level floor. If the frictional force is 80 newtons. What is the magnitude of the northward

Gravitational self energy, It is the energy possessed by a body because of ...

It is the energy possessed by a body because of the interactive forces inside the object. This may be defined as the work done in assembling all the particles of a body in a exact

Soft and hard magnetic materials, Magnetic materials are divided in terms o...

Magnetic materials are divided in terms of their magnetic properties and their applications. If a material is effortlessly magnetized and demagnetized, then it is known to as a sof

Blow holes and porosity, What is the difference between blow holes and poro...

What is the difference between blow holes and porosity

Determine the velocity of a wave frequency, The frequency of a wave is 50 H...

The frequency of a wave is 50 Hertz and its wavelength is 25 meters. What is the velocity of this wave? Ans: The velocity of given wave is 1250 meters/second.

What locations on the sticks to make it balanced, Here's what is given: A....

Here's what is given: A. There are three 1 meter sticks B. There are four weights: Weight #1 = 1kg Weight #2 = 1.2kg Weight #3 = 1.5kg Weight #4 = 2kg The sticks don't hav

Illustrate what are the characteristics of dead stars, Q. Illustrate what a...

Q. Illustrate what are the characteristics of dead stars? Answer:- Dead stars are typically cold balls of material in empty space. A teaspoonful of white dwarf substance w

Assuming electrons as classical particals, If electrons are treated as clas...

If electrons are treated as classical particles,which statistics will they follow?

State the principle of working of p-n diode as a rectifier, State the princ...

State the principle of working of p-n diode as a rectifier. Describe, with the help of a circuit diagram, the use of p-n diode as a full wave rectifier. Illustrate a sketch of the

Free-particle, Free-particle A.  Suppose that the wavefunction for a f...

Free-particle A.  Suppose that the wavefunction for a free-particle is given by the wavefunction Find the value of A that normalizes Ψ (x). B.  The Hamiltonian oper

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