Question

the heat energy transfered from one body to another body is 21J its value in calories is(1cal=4.2J)​

Answer 1

Answer:

hey mat

Explanation:

1 calories is equal to 4.184 Joules simply because it is defined as such. The original definition of a calorie is the amount of energy needed to raise one gram of water by 1 degree Celsius, but this is variable based on starting temperature or pressure, so 1 calorie was just defined to be exactly 4.184 Joules