Teacher : Today we'll learn energy, do you know what is the unit of energy?
Student : joule sir!
Teacher : Another possible unit?
Student : Calorie sir?
Teacher : You have 5 joule of energy. Could you convert in calorie?
Student : Yes sir, 1 joule = 0.24 calorie or 1 calorie = 4.2 joule so then I have 5 x 0.24 = 1.2 calorie of energy.
Teacher : 1.2 calorie or 1.2 calories ?
Student : 1.2 calorie sir, if we use 1.2 calories for expressing that, the "s" in physics mean second sir, so I think its better to use 1.2 calorie than 1.2 calories to avoid wrong interpreting.
Teacher : Ok, enough for today see you tomorrow, don't forget to bring your homeworks!
