A Clock is a circular device provided with three hands viz. an hour hand, minute and second hand. The study of the clock is known as “horology”.
[ A basic structure of a clock with three hands ]
A clock is composed of 360 degrees and divided into 12 equal divisions. The angle between the consecutive divisions is obtained by dividing the total angle of clock 360° by the number of divisions i.e. 12.
[Twelve equal divisions of a clock]
# The angle between any two consecutive divisions = (360°)/12= 30°
[Angle divisions of a clock]
A close observation of a clock reveals that an angular space between any two consecutive divisions has further five more divisions. The area between the two divisions corresponds to a value of 5 minutes. Hence, diving the 30° by five will result in the angular value of a minute.
Angular value of a minute = (30°)/5= 6°
[Angular values of minutes]
The table given below demonstrates the angular values of the first ten minutes:
Clocks is easy to learn - You will enjoy it.
Clocks problem classified into four module:
Explanation: We know for (1hour/60min), Min=360 degree &Hours=30degree.For (1min),Min=6degree,Hour=1/2degree.In 4:12, 4hour 12min is (4*30)+12/2-(12*6)=54degree.
A) 85 degree
B) 90 degree
C) 105 degree
D) 95 degree
Answer:D) 95 degree
Explanation: By putting formula A=mod(30(H)-11/2(M)), here H=5, M=10 so A=95degree