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Half Time At 3:00 the hour hand and the minute hand of a clock point in directions that are 90.0 apart. What is the first time after 3
Question
Half Time At 3:00 the hour hand and the minute hand of a clock point in directions that are 90.0
apart. What is the first time after 3:00 that the angle between the two hands has decreased by half to 45.0?
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Physics
4 years
2021-08-31T12:32:06+00:00
2021-08-31T12:32:06+00:00 1 Answers
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Answers ( )
Answer:
3 : 08 : 10.9
Explanation:
assuming a 12 hour clock
angular velocity of the hour hand is 2π/(3600(12)) rad/s
angular velocity of the minute hand is 2π/3600 rad/s
difference is 2π/3600 – 2π/(3600(12)) = 11(2π/(3600(12)) rad/s
45° = π/4 radians
This angle is covered in a time of
π/4 rad / 22π / (3600(12)) = 900(12) / 22 = 490.909090… s
or about 8 minutes 10.9 s
ANSWER 3:08:10.9