Why heat is directly proportional to resistance when current and time are constant?

Question

Answer

Bcuz H=I^2RT if I=current and T=time is constant H will directly proportional to R= resistance. you can also say that heat will increase if we increase material's length and heat will deacrease if we increase material's cross section area and we knw tht Resistance = rho×length / cross sectional area... so heat will be directly proportional to R means resistanceif i and t will nt constant then obviously H will be directly proportional to I , R & T

Answer

When temperature increases or heat increases the lattice structure of a conductor starts to vibrate rapidly ,in order to move from this high vibrating structure electrons have to move quickly as possible , in this race of electrons as the electrons rapidly collide with each other and due to this rapid collisions some electrons are thrown in opposite direction hence output of electrons decreases and current also decreases and so RESISTANCE INCREASES

Answer

Explanation: Heat and Resistance

When an electric current flows through a conductor, the electrons in the conductor collide with the atoms and molecules that make up the conductor. This collision causes resistance, which is the opposition to the flow of electric current. When resistance is present, some of the electrical energy is converted to heat energy, which is dissipated into the surroundings. The amount of heat generated depends on the resistance of the conductor, the current flowing through it, and the time for which the current flows.

Direct Proportionality of Heat and Resistance

When the current and time are constant, the amount of heat generated is directly proportional to the resistance of the conductor. This can be mathematically expressed as:

Q = I²Rt

Where Q is the heat generated, I is the current flowing through the conductor, R is the resistance of the conductor, and t is the time for which the current flows. From this equation, it can be seen that if the current and time are kept constant, then the amount of heat generated is directly proportional to the resistance of the conductor.

Example

For example, consider a conductor with a resistance of 10 ohms through which a current of 2 amperes flows for 5 seconds. The amount of heat generated in the conductor can be calculated as:

Q = (2)² x 10 x 5

Q = 100 joules

Now, if the resistance of the conductor is increased to 20 ohms while keeping the current and time constant, then the amount of heat generated will be:

Q = (2)² x 20 x 5

Q = 200 joules

Thus, it can be seen that the amount of heat generated is directly proportional to the resistance of the conductor when the current and time are kept constant.

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