① The included angle between the minute hand and the hour hand is180; ② The included angle between the minute hand and the hour hand is 0, that is, the minute hand coincides with the hour hand.
Xiaoming solved a problem between 7 and 8 o'clock. At first, the minute hand and the hour hand were just in a straight line. When the problem is solved, both hands coincide. When did Xiao Ming start to solve the problem? How long did it take Xiao Ming to solve this problem?
The hour hand and minute hand of a clock are between 4 and 6, and the word "5" on the clock face is right in the center of the hour hand and minute hand. What time is it now? Because it can be more than 4 o'clock or more than 5 o'clock now, the discussion is divided into two situations: ① Let this time be more than 4 o'clock; (2) this time let it more than 5 o' clock.
When do the two needles coincide between 4.6 and 7 o'clock?
5. It's two o'clock, 15. In a few minutes, the hour hand and the minute hand coincide for the first time.
At what time between 6.7 o'clock and 8 o'clock (including 7 o'clock and 8 o'clock), the angle between the two needles is 120?
7. Uncle Li is going to work in the factory at 3 pm. It's probably time for him to go to work. He went to the house to look at the clock, which had already stopped 12: 08+00. He forgot to set the needle after winding up and left home in a hurry. When he arrived at the factory, he saw that there were still 10 minutes before going to work. Work 8 hours, at night 165438+.
8. The two hands on the surface of the old clock overlap every 66 minutes. How many minutes is this old clock fast or slow in the standard time?
Find the degree of the angle formed by the hour hand and the minute hand in the next time. (1)9 o'clock sharp (2) 2 o'clock sharp (3)5: 30 (4) 10: 20 (5)7: 36 2. How many minutes have passed since the hour hand points to 4 o'clock and the hour hand coincides with the minute hand? 3. A few minutes after 3 o'clock on the clock face, (1) the hour hand and the minute hand coincide? When is the next coincidence of the hour hand and the minute hand? (3) Is the number of angles formed by the ray where the hour hand and the minute hand are located equal to the connecting line from the center to the word "3"? Between one o'clock and two o'clock, when does the minute hand and the hour hand form a right angle? 5. When do the hour hand and minute hand of the clock coincide and are perpendicular to each other between 3 o'clock and 4 o'clock? 6. When does the angle between the minute hand and the hour hand of a clock become 180 degrees between four o'clock and five o'clock? 7. Someone went out after 6 pm. He looked at his watch and the angle between his two hands was 1 100. When he got home before 7 pm, he found that the angle between his hands was still 1 100. Q: How long has he been out? 8. It is an instant between 10 and 1 1. After 6 minutes, the minute hand position and the three-minute position just form an included angle of 1800. What time is it now? 9. The hour hand and minute hand of a small square watch overlap every 66 minutes. How many minutes is his watch faster than the standard clock every day and night? 10, Xiaohong has a clock, which is 2 minutes slow every hour. At 8 o'clock in the morning, Xiaohong set the clock to the standard time. Then, when the clock strikes 12, is the standard time 12: 08? Why? 1 1. My mother bought a watch for Wang Minxin. Wang Min found that this watch is 30 seconds faster than the wall clock at home. However, the wall clock at home is 30 seconds slower than the standard time every hour. So, do you think Wang Min's new watch is accurate? Why? Between 12, midnight 12:00 and noon 12:00, how many times did the minute hand on the clock make right angles to the hour hand? 13. Suppose there is a straight line on the clock face, which passes through "6" and "12" on the clock face. At a certain moment, the angle between the hour hand and the minute hand is divided into two by this straight line. At this time, we call it "symmetry" of two needles. How many times are the hour hand and the minute hand * * * "symmetrical" a day? When are they?