How are both screw and wedge inclined plane?

Find four types of simple machines from the following word puzzle.

Recall and complete the concept map given below.

Choose the right word from the given options:

Simple machines are of _____ (two, six) types.

Complete the concept map.

Read the clues and fill up the crossword:

Across:

1. A nail with grooves.

2. A push or pull.

3. A rod fixed at one end.

4. A wheel that rotates with a rope.

5. Method to reduce friction in machines.

Down: 

6. A wheel that spins on a bar.

2. A force that stops movement.

7. A change bought by applying force.