What kind of motion is executed by a spin ball?

State three precautions to be taken to measure the length of an object using a meter scale.

Why are the co-passengers in a train appear to be stationary, while the trees outside appear to move to a passenger sitting in the train?

A turning screw undergoes two kinds of motion at the same time. Identify the two kinds of motion.

A student has to measure the length of his pencil. The zero mark on the scale is not clearly visible. How should he/she use the scale to get the correct length of the pencil?

Complete the puzzle with the help of the clues given.

ACROSS:

$1$. Motion of a stone tied to a string and revolving.$\left(8\right)$

$2$. Motion of a football during the game. $\left(6\right)$

$3$. The movement of a drill. $\left(7\right)$

DOWN:

$4$. Measuring device used for measuring the length of a curved line. $\left(7\right)$

$5$. Small and rapid to-and-fro motion.$\left(9\right)$

$6$. Property which repeats itself at a regular interval. $\left(8\right)$