Heat produced in electric current is dorectly or inversely proportion to resistance
Heat is produced through friction.
Resistance is the opposition to the movement of charged particles.(i.e high resistance the charged particles bang into stuff and results in collisions)
These collisions gives rise to heat.
So, higher resistance=More collisions = more heat.
Comparison for :
1. H=I^2 RT
Here we cant said that H is proportional to the square of I .
Actually, H is proportional to product of square of I and R.There are 3 terms namely I, R and T.
I and R are related ( that is ohms law).But T remains independent of I and R.
In the second equation , V and R are related.
In the third ,V and I are related.
When the terms are related in an equation , it is difficult to said the dependence of one term (here H) with a single term( V, i or R).Because the single term is related to the other .But when the conditions are specified u can find the dependence.
Suppose R is constant ( u fixes the resistance constant), then H is proportional to I2.(since Rt is independent of I)
In second equation,under same condition, H is proportional to V2
In the third H is proportional to product of V and I.