Always do this before you try to answer a question on a worksheet or a test.

I would have thought it was obvious but it wasn’t obvious to (at least) three Year 11 Physics students in a class of about 20.

I had just finished teaching them the Law of Refraction using LEM’s Shedding Light on Refraction program. The bonus feature on this program explains how to calculate the angle that light will refract when it passes from one transparent medium to another. I then gave them the The Law of Refraction Worksheet. The worksheet has a list of formulas and other data. Here is a screen shot of part of the worksheet.

Question 3 asks:
A ray of light travels from air to glycerol at an incident angle of 38° and is refracted at an angle of 24.6°. What is the refractive index of glycerol?

Two students over the span of about two minutes asked the same question which was basically, “Sir, can you help me with this? I don’t know the refractive index of glycerol.”

Neither of them had read the question!!

Just as I was telling the second student that it’s the refractive index of glycerol that they needed to find, I heard another student (a third student) ask the same question to one of his mates.

I’ve been using this worksheet for years now and this had never happened before, but I thought this was a golden opportunity for an important teaching moment and I immediately stopped the whole class.
“Three students have just asked about question 3. They got confused because they didn’t know the refractive index of glycerol. This might sound a little crazy, but before you try to answer a question, you should always READ THE QUESTION first!!!”

A colleague of mine served as a Year 12 examiner for the Year 12 Chemistry exam for many years. A few years ago he told me that students routinely didn’t read the question in full before writing down their answers.
A common mistake was to answer only part of the question when the question was clearly in two parts. Another common mistake was to focus on a particular word in the first sentence of a question and then assume that the question was related to the definition of that word.

So, in summary,
STEP1: Read the Question
STEP 2: Answer the Question.

Never attempt to do it the other way around.

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