How many large cells are there in a **** on a clock dial?

***12 big grid, each big grid divided into 5 small grid, the hour hand to go a small grid is 12 minutes, go a big grid is an hour; minute hand to go a small grid is one minute, a big grid is 5 minutes; second hand to go a small grid is one second, go a big grid is five seconds.

The clock has a variety of structural forms, but its principle of operation is basically the same, are composed of the original system, transmission system, escapement governor, the hands of the system and the upper bar toggle needle system and other parts.

Expanded Information

Time units of conversion relations:

(1) a day = 1440 minutes, 1 hour = 60 minutes, 1 minute = 60 seconds.

(2) A moment = 15 minutes, a word = 5 minutes (used in southern Fujian and Guangdong).

Angular relationship between the hands of the clock:

(1) ordinary clock is equivalent to a circle, its hour hand or minute hand to go round are equivalent to go through 360 ° angle.

(2) Each large frame on the clock corresponds to an angle of 30°.

(3) The angle corresponding to each minute traveled by the hour hand is 0.5°

(4) The angle corresponding to each minute traveled by the minute hand is 6°.