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Anonymous users2024-02-071. The student ran for 40 minutes.
2. Your question is a bit of a problem, if the railway is 1000 meters long, it can't be answered; If the railway bridge is 1000 meters long and the train passes over the railway bridge, the speed of the train is meter seconds = kilometers and hours.
1. Before going out, the angle between the minute hand and the hour hand is 110 degrees, and the minute hand is set to point to the digital x
There is an equation: 30 60*x+(15-x)*6=110-90, and x=140 11
That is, the time to go out is 6:140 11.
When you get home, if the angle between the minute hand and the hour hand is 110 degrees, then the minute hand points to the digital Y
There is an equation: (30-30 60*x)+(x-50)*6=110-90, and y=580 11
That is, the time to return home is 6:580 11 a.m.
Then the student's running time is 580 11-140 11 = 40 minutes.
2. Set the train length to be x meters.
Then there is the equation: (1000+x) 60=(1000-2x) 40, which gives x=125 meters.
v = 1125 60 = meters seconds = kilometers hours.
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Anonymous users2024-02-06Just calculate the angle of the minute hand to see how little time it took.
The angle between the minute hand and the hour hand is 110 degrees twice, but when the minute hand walks, the hour hand moves in a number of degrees of 1 12 minutes, so the angle of the minute hand is: 110 + 110 + the angle of the hour hand (the angle of 110 degrees in the second time).
Set the angle of the hour hand to x
x/(110+110+x)=1/12
x=20 so the angle of the minute hand is: 110 + 110 + 20 = 240 degrees.
A circle is 360 degrees and 60 minutes, so the time used is: 60 * 240 360 = 40 minutes.
By the way, the clock is divided into 60 squares, and when the minute hand goes 60 squares, the hour hand goes 5 squares, so the ratio of the hour hand to the minute hand is 1 12
When the angle between the minute hand and the hour hand is 110 degrees, the hour hand is walking, so the angle of the minute hand must be added to the angle of the hour hand, so the angle of the minute hand is: 110 + 110 + the angle of the hour hand (the angle of 110 degrees in the second time).
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Anonymous users2024-02-05Analysis: (1) The angle between the hour and minute hands at 6 o'clock is 180°.
2) The minute hand goes 360° per hour, and the hour hand moves 360° every hour 12=30°.
3) The first minute hand is 110° with the hour hand to the second time the hour hand is 110°, the minute hand is 2*110° longer than the hour hand, and it takes 2*110° (360°-30°) = 2 3 hours = 40 minutes. This is also his time to run.
Solution: Set up to run for x points.
x=40 minutes.
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