Question

Convert Joule to calorie 1J =
A. 4.18 calorie
B. 2.4 calorie
C. 0.24 calorie
D. 100 calorie

Answer 1

Hint: Joule: Joule is SI unit of energy. If it is equal to work done by unit force (Newton) through a distance of one meter.
Calorie: Amount of energy required to raise temperature i.e. unit gram of water 60 unit degree at unit atmospheric pressure.
$$\text{1 cal=4}\text{.184 J}$$

Complete step-by-step answer:
By relation between calorie and Joule we can write
$$\Rightarrow \text{4}\text{.184 J=1 cal}$$
$$\Rightarrow \text{1 J = }{\displaystyle \frac{\text{1}}{\text{4}\text{.184}}}\text{cal }$$
$\Rightarrow \text{1J=0}\text{.239005cal}$
$\Rightarrow \text{1J=0}\text{.24cal}$
Hence, the answer is option c.

Note: Calories are of following types:
Small calories:- If the amount of energy required to heel unit grams to unit Celsius at unit atmospheric pressure it is generally represented in small cal.
Large calories: it is the amount of energy required to 1 kg to $$1{}^{\circ }C$$at 1 atm pressure. These are generally represented in caps (cal). These are also known as food calories relation between small and large.
$$\text{1 large calorie = 1 kilogram small calorie}$$
We generally consider large calories calories.
To convert $$\text{(}\underset{j}{E}\text{)}$$Joules to calories
$$\underset{cal}{E}={\displaystyle \frac{E(cal)}{4.184}}calories$$
And to convert $$\text{(}\underset{cal}{E}\text{)}$$to $$\text{(}\underset{j}{E}\text{)}$$
$$\underset{j}{E}=4.184\times E_{cal}$$