The document discusses angles between clock hands and times when they coincide. It contains: 1) Questions about angles between hands at specific times and when they coincide between hours 2) Explanations of clock angles - hour hand moves 30° each hour, minute hand 5° each minute 3) Solutions to questions using |30h - m| formula to find angles and setting 30h = m to find coincidence times 4) Practice problems are provided to calculate angles and coincidence times for different clock hands.

1. Clocks
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2. 1. What is the angle between minute hand and hour hand at 3:25?
2. At what time between 4 and 5 the minute hand and hour hand coincide?
3. After a regular interval of how many minutes, do the minute hand and
hour hand coincide?
4. At what time between 11 and 12 the minute hand and hour hand
coincide?
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3. • The total angle in a clock = 360
• The circumference of the clock is divided into 12 equal parts called hour
spaces.
• Angle in each hour space = = 30 = 60min.
 1min =
• Each hour space is divided into 5 min space.
• Angle in each min space = 6
• In one hour, the hour hand rotates through an angle of 30
• In one minute, the hour hand rotate
• The angle between min and hour hand at hh:mm is |30h - m|
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4. What is the angle between minute hand and hour hand at 3:25?1.
The angle between min and hour hand at 3:25 is 47.5
Ans:
The angle between min and hour hand at hh:mm is |30h - m|
 H =3 , m = 25
 90 – 275/2
 47.5
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5. At what time between 4 and 5 the minute hand and hour hand coincide?2.
The minute hand and hour hand coincide at 21
Ans:
The angle between min and hour hand at hh:mm is |30h - m|
 30h = m
 60h = 11m
 m =
 m = 21
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6. At what time between 4 and 5 the minute hand and hour hand are
opposite to each other?
2a.
Minute hand and hour hand are opposite to each other at 54
Ans:
The angle between min and hour hand at hh:mm is |30h - m|
 30h - m = -180
 60h + 360 = 11m
 m =
 m = 54
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7. After a regular interval of how many minutes, do the minute hand and
hour hand coincide?
3.
Ans :
The angle between min and hour hand at hh:mm is |30h - m|
 30h - m = 0
 60 * 12 = 11m
 m =
 m = 65
The minute hand and hour hand coincide regularly after a period of 65
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8. At what time between 11 and 12 the minute hand and hour hand are
coincide?
4.
Ans :
The angle between min and hour hand at hh:mm is |30h - m|
They will never coincide between 11 & 12 and 12 & 1.
The minute hand and hour hand coincide at 12:00.
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9. Subscribe to :
Problems for practice are given in the description of the video.
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10. 1. What is the angle between minute hand and hour hand at 1:20?
2. What is the angle between minute hand and hour hand at 5:15?
3. At what time between 9 and 10 the minute hand and hour hand coincide?
4. At what time between 7 and 8 the minute hand and hour hand a)
coincide b) opposite c) at right angle ?
5. In 12hrs, how many times the minute hand and hour hand coincide?
Practice:
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