Wheels

This task is about how wheels work.
These pictures show four stages in the development of the wheel over time.
wheels-A.png
Wooden-spoked wheel
Wheels-B.png
Wooden disc wheel 
Wheels-C.png
 Wooden wheel with iron rim
Wheels-D.png
Metal-spoked wheel 

Question

a)  Which of these wheels would have been developed first?

    • wheels-A.png
      Wooden-spoked wheel

    • Wheels-B.png
      Wooden disc wheel

    • Wheels-C.png
      Wooden wheel with iron rim

    • Wheels-D.png
      Metal-spoked wheel

Question 2Change answer

b)  Give one reason why spoked wheels are better than the wooden disc wheel.
     

Question 1Change answer

Wheels-C.pngWooden wheel with iron rim
c)  Why is an iron rim put around the wooden-spoked wheel?
     

Question 1Change answer

d) Old cars had solid rubber tyres. Modern cars have air-filled rubber tyres. 
i) What is an advantage of air-filled tyres? ii) What is a disadvantage of air-filled tyres?