Earliest time piece in record
Water clock
Sundial
pocket watch
Sand clock
Water clock is the earliest time piece in record
Everyone uses watch to keep track of time. Nowadays most people use digital watches but that hasn't discredited the style of the conventional clock with hands. The angle formed by the hands of a clock at 6:00 pm is a __________.
Two clocks are set to show the correct time at 1:00am on a day. One clock loses 3 minutes in an hour and the other clock gains 3 minutes in an hour. Exactly after how many days will both the watches show the correct time? Assume that is a 12 hour clock.
What is the principle of a sand clock?