A CD has a small radius of 25 mm and a larger radius of 58mm. The tracks on the CD are 0.5micro meter thick and 1.6 micrometer apart.
Q1) How many tracks are there?
Q2) Prove that the total length of the tracks is 5km.
BTW, here is another one which was in my finals:
You have to investigate how the force of friction acts on different brands of shoes.
you are provided with a string attached to the shoe.
Q1) Give three essential pieces of apparatus which would be required to carry out the investigation and state why they are important.
Q2) How would you carry out the investigation?
Q3) Give two reasons why the results of this investigations cannot be applied to real life running?