An elastic cord vibrates with a frequency of 3.0 Hz when a mass of 0.60 kg is hung from it. What is its frequency if only 0.38 kg hangs from it?

Solution Step 1 Establishing what is calorific value. Calories are units of energy similar to joule. There are two categories for calories and they are small calorie (mainly used for thermochemical reactions) Large calorie or food calorie (For large energy calculations) Small calorie is represented using the unit “cal”. Large calorie is represented using the unit “Cal”. 1 large calorie = 1000 small calories Or, 1 Cal = 1000 cal. Here, we should use the large calorie for the energy calculation in food. Step 2 Converting small calorie to joules 1 small calorie is equivalent to 4.184 joules That is, 1 cal = 4.184 joules X small calorie = (X × 4.184) joules