Question

V = IR I = V/R W = VQ POWER = Work Done/Time P = VQ/t P = V X Q/t P = V X I P = VI Work Done = POWER X Time Work Done = VI X t Work Done = VIt Work Done = Energy. Therefore , H = VIt Using V = IR H = IR X It H = I²Rt Using I = V/R H = VIt H = V X V/R X t H = V²t/R Now, H = VIt H = I²Rt H = V²t/R My Questions (i) When to use which formula ? (ii) Is RESISTANCE DIRECTLY OR INVERSELY PROPORTIONAL TO HEAT PRODUCED ? (iii) I am facing similar problem in other quantities (in V and I). Are they DIRECTLY OR INVERSELY PROPORTIONAL TO HEAT PRODUCED ?

Answer 1

Answer:

You have to use the particular formula when one of the variables in the formula are missing and you are asked the variable missing.With whatever values u have ur supposed to use the formulas.Resistance is directly proportional to heat produced like a filament lamp.But in the case of a thermistor it is inversely proportional.According to ohms law voltage is directly proportional to current if voltage is constant.This is only true if the material is an cosmic conductor and wont apply if it's a nontoxic conductor