**Question**

**50.4 joule of work is needed to produce 12 cal of heat. Find the value of Joule’s constant. [Ans. 4.2 J/cal] **

**Answer**

To find the value of Joule’s constant, we can use the equation:

Joule’s constant (J) = Work done (in joules) / Heat produced (in calories)

Given:

Work done = 50.4 joules

Heat produced = 12 cal

J = 50.4 J \over 12 cal

Converting calories to joules: 1 cal = 4.186 J

J = 50.4 \over(12 × 4.186)

J ≈ 4.2 J/cal

Therefore, the value of Joule’s constant is approximately 4.2 J/cal.