Practice UPSC CSAT previous year questions from 2011–2026 classified underClocks. Review the original question, four options, correct answer and explanation for every PYQ.
5 questions • 2011–2026
How many times do the hour hand and the minute hand coincide in a clock between 10:00 a.m. and 2:00 p.m. (same day)?
Coincidences occur about every 65 5/11 minutes. Between 10 a.m. and 2 p.m. they occur three times: around 10:54, 12:00 and 1:05.
What is the angle between the minute hand and hour hand when the clock shows 4:25 hours?
At 4:25, the minute hand is at 150° and the hour hand at 132.5°. The difference is 17.5°.
There are three traffic signals. Each signal changes colour from green to red and then red to green. The one-way intervals are 25, 39 and 60 seconds and green/red durations are equal. At 2:00 p.m. they turn green together. When will they next turn green together?
Full cycles are 50,78,120 seconds; LCM=7800 seconds=130 minutes, so 4:10 p.m.
Consider the following statements: 1. Between 3:16 p.m. and 3:17 p.m. both hour hand and minute hand coincide. 2. Between 4:58 p.m. and 4:59 p.m. both minute hand and second hand coincide. Which of the above statements is/are correct?
The hour and minute hands coincide at about 3:16:22. The minute and second hands coincide at about 4:58:41, so both statements are correct.
Between 6 PM and 7 PM the minute hand of a clock will be ahead of the hour hand by 3 minutes at
At 6:t, the minute hand leads the hour hand by 3 minutes when 5.5t−30×6 = 18 degrees; solving gives t=36 minutes.
Attempt questions one by one with UPSC-style marking and immediate explanations.