A student wants to measure the outer diameter of a cylindrical wooden rod as accurately as possible. Which of the following sets of apparatus is needed to get an accurate measurement?
a ruler and a protractor
a ruler only
a protractor and a set-square
a ruler and two rectangular blocks
164 exam-style questions on CIE IGCSE Physics Physical quantities and measurement techniques, covering Physical quantities and measurement techniques. Each one has a worked solution and a mark scheme showing where the marks go.