Question

07. According to Joule's law of heating which statement is wrong:
A. Heat is produced in a resistor is directly proportional to the current.
B. Directly proportional to resistance.
C. Directly proportional to the time for which the current flows through the resistor.
D. Directly proportional to the square of current for a given resistance.​

Answer 1

$\huge\star{\green{\underline{\mathfrak{Answer :-}}}}$

According Joule's law of heating the statement A is wrong.

$\rule{200}2$

What is Joule's law of heating ?

The joules law of heating states that the energy produced in a current carrying conductor or the heat developed when the current passes through the conductor is:

• Directly proportional to the square of the current in the conductor.
• Directly proportional to the resistance of the conductor.
• Directly proportional to the time for which the current flows through the conductor.

Hence, H = I²Rt

$\rule{200}2$

So, with the help of the definition of Joule's law of heating, we can conclude that statement A is a false one.

$\rule{200}4$

Answer 2

Question

According to Joule's law of heating which statement is wrong:

A. Heat is produced in a resistor is directly proportional to the current.

B. Directly proportional to resistance.

C. Directly proportional to the time for which the current flows through the resistor.

D. Directly proportional to the square of current for a given resistance.

Solution

$\huge{\sf Joule's \ Law \ Of \ Heating \colon}$

The heat energy generated in a conductor is directly proportional to the

• Square of the current flowing through the conductor

• Resistance in the conductor due to the current flow

• Time in which the curent flows

If current I flows through a conductor in time T with a resistance R,then heat evolved would be :

Mathematically,

$\boxed{\boxed{\tt H = I^2 RT}}$

Thus,I conclude option (A) is false