A screw is a simple machine that appears like an inclined plane wound around a rod with a pointed tip.
Examples, a jar lid, a drill.
(a) What is meant by a solution ? Give two examples of solutions.
(b) What is suspension ? Give two examples of suspensions.
(c) What is a colloid ? Give two examples of colloids (or colloidal solutions).
(a) What is a physical change ? Give two examples of physical changes.
(b) What is chemical change ? Give two examples of chemical changes.
(a) What is the noise? Give two examples of sounds which are considered noise.
(b) What is a musical sound? Give two examples of musical sounds.