Aptitude Clocks Test Paper 11) How many times the hands of a clock coincide in a day?
The Correct answer is (B) Explanation: The hands of a clock coincide only once between 11 O' clock and 1 O' clock, so in every 12 hours, the hands of a clock will coincide for 11 times. ∴ In a day or 24 hours, the hands of a clock will coincide for 22 (11+11) times. 2) At what time between 3 and 4, the hands of a clock are straight and point in opposite directions?
The Correct answer is (C) Explanation: At 3 O' clock, the hands of the clock are 15 minute spaces apart. To be in straight line and in opposite directions, the hands must be 30 minutes spaces apart. Now, the minute hand is 15 minute spaces behind the hour hand, so it has to gain 45 (15+30) minute spaces over the hour hand. 55 minute spaces are gained in 60 minutes by the minute hand 45 minutes will be gained in =* 45 minutes minutes past 3. Solution 2: Apply formula: (5H + 30) minutes past H, when H < 6 As per the question, H = 3 O' clock Required time = (5*3 + 30) =(15+30) =45 *
3) An accurate clock indicates 8 O' clock in the morning. Through how many degrees the hour hand turns when the clock indicates 3 O' clock in the afternoon?
The Correct answer is (A) Explanation: There are 7 hours between 8 O' clock in the morning and 3 O' clock in the afternoon. Now, angle traced by the hour hand in 12 hours = 360° ∴ Angle traced by the hour hand in 7 hours = 4) What is the angle between hour hand and minute hand of a clock at 3.30?
The Correct answer is (C) Explanation: Angle traced by the hour hand in 12 hours = 360° Angle traced by the hour hand in 3 hours 30 minutes =
Angle traced by minute hand in 60 minutes = 360° Angel traced by minute hand in 30 minutes = ∴ Required angle would be = (180  105)° = 75° 5) At what time between 4 o'clock and 5 O' clock will the hands of a clock coincide?
The Correct answer is (A) Explanation: At 4 O' clock, the minute hand is 20 minute spaces behind the hour hand. To coincide with the hour hand, it has to gain 20 minute spaces. Now, 55 minute spaces are gained by the minute hand in 60 minutes 20 minutes will be gained in ∴ The hands will coincide at 21 minutes past 4. Solution 2: Apply formula: minutes past H O' clockNow, H = 4 O' clock ∴Required time =
