Question

The problem is not difficult but it confuses me that sometimes it is divided by 1.8 or multiplies. What is this? How to know when it is multiplied by 1.8 or divided by 1.8? please explain to me, while you solve the problem please do not skip steps and write because you do the steps, write big please because sometimes I can not see the letters please

The efficiency of a refrigerator increases by 3 for each C increase in its minimum temperature. What is the efficiency increase for each a) K, b) ºF and c) R of temperature increase?

These formulas I used for pressure difference

(https://plus.google.com/photos/photo/115413650822843498915/6534619848310315426?authkey=CJOx8p3Hqe_WAQ&hl=es)

Answer 1

This is a common confusion. Lets look at any measurement, say 5 kg. It is made up 2 parts: a value (or the number 5) and a unit which represents a standard amount of the quantity we are measuring. Think of this as 5 times the standard unit (or 5 multiplied by 1 kg). Now, consider a smaller unit-gram. A gram is (1/1000)th part of a kilogram. To represent 5 kg in grams, should we write (5/1000) g ? This is where we go wrong! Isn’t (5/1000) g = 0.005 g very small as compared to 5 kg. We had to rather multiply by 1000. This is 5 kg = 5000 g. Hence, when the unit becomes smaller the value multiplied becomes larger such that the application of the two gives the same result.

In case of temperature F and R are smaller units (1.8 times smaller) than C and K. Example 1 K = 1.8 R and similarly 5K = 9R

The formulas for temperature difference that you have shared are correct. In case you need more help, let me know.