Physics Paper 2,LAst Q resistance!!

[khan_123]

please tell the value of your resistance and alaso how did you calculate it!!!

 

[Hashim]

p.d across the fixed resistor = 3.8 V
Resistance was 2000 ohms

current = v/R
= 0.0019 A

current across the thermistor = 0.0019 A
p.d across the thermistor = 6-3.8 = 2.2 V

Resistance = V/I
= 2.2 divided by 0.0019
= 1158 ohmx

 

[beststriker]

@ hashim ya right....!!!!

 

[OakMoon!]

There were 2 methods to solve this Q... U cud do it by the proportion of voltage too... i showed both workings....

 

[Hiranand]

On the dot Hashim ! correct!

 

[Hashim]

yup...thnx

you could also do this by applying the potentiometer principal...!! but alll izz well

 

[xcalibur]

Although the answer is correct, the working is not.
Ohms law can only be applied when physical conditions are constant, the temperature was changing here.. so it is not fully correct to use Ohms law.
The R1 over R1+R2 was the better way to solve the question.. but i think that would be accepted as well as I got the same answer.