1.Fill in each blank with the word that fits best.Choose from the words below .
rotate simple machine wheel axle once twice greater smaller
A doorknob is a___________________________________.
The knob is the ___________________________.
The shaft is the______________________.
If the knob turns once, the shaft turns_____________________________.
The diameter of the wheel is always_________________________ than the diameter of the axle.
II.Which statement seems more likely to be true? (Write True in the blank if you think it is true)
A. ______A tire is a simple machine.
B. ______ A hand mixer is a simple machine.
III. A doorknob has a diameter of 6 cm. The shaft has a diameter of 2 cm. Find the mechanical advantage of the doorknob.
MA=__________________ 
