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

For 9th, can i get this job?

can i get this job?

Calculate the final intensity, Randomly polarized light (such as sun light)...

Randomly polarized light (such as sun light) with intensity of I 0 passes through three polarizers (P 1 , P 2 , P 3 ) consecutively.  P 1 and P 3 are stationary, and their polar

Predict the strain measurement returned by strain indicator, A thin isotrop...

A thin isotropic metal plate is subjected to the plane stress state shown (properties of the metal are: E = 10x10 6 psi and ν = 0.250). A uniaxial strain gage is mounted on the pl

Mechanical properties of solids, Assignment of applications of elastic beha...

Assignment of applications of elastic behaviour of materials

Electrostatics, Can ever the whole charge of a body be transferred

Can ever the whole charge of a body be transferred

The effects of the angle of the sun''s rays, Demonstrating the effects of t...

Demonstrating the effects of the angle of the sun's rays on the quantity of heat and light received by the earth Bend a piece of cardboard and make a square tube 4 cm2 in cros

Define the centripetal acceleration, Two bodies are moving in circular path...

Two bodies are moving in circular paths of equivalent radii.  If the speed of the first body is twice that of the second, the centripetal acceleration of the first body is how

Determine the net force, Q. While rummaging in her backpack for her cell p...

Q. While rummaging in her backpack for her cell phone, Sally's Mini-Cooper rear ends Joey's Suburban. Sally's car is totaled while the suburban is fine. If Sally's car hit the sub

How cph takes spin and converts to graviton, How CPH takes spin and convert...

How CPH takes spin and converts to graviton? Answer- A CPH Principle says a CPH moves with constant speed as Vc, Vc>c in any inertial frame and any space, therefore that

Plot the waveform - signal of amplitude, 1. You are trying to observe a 500...

1. You are trying to observe a 500 Hz signal of amplitude 2 mV in the presence of an interfering 4.0 kHz signal also of amplitude 2mV. Use a MATLAB .m script to plot the waveform y

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