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प्रश्न
The basic unit of time is second.
विकल्प
True
False
उत्तर
This statement is True.
Explanation:
The basic unit of time in the International System of Units (SI) is the second.
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संबंधित प्रश्न
Tick the most appropriate answer.
A train departs from Delhi railway station at 21:50 hours every day. The time shown in your analog watch at the departure will be
Fill in the blank.
The first two digits in a 24-hour time format represent the number of ............
Define time.
The national physical laboratory is located in Delhi.
In earlier days, which instruments are used to measure time?
What are the clocks used to measure a smaller duration of time?
Which alloy is used to make the standard meter rod?
Assertion (A): The SI system of units is the improved system of units for measurement.
Reason (R): The SI unit of mass is the kilogram.
Assertion (A): The skill of estimation is important for all of us in our daily life.
Reason (R): The skill of estimation reduces our consumption of time.
You can make your own sundial and use it to mark the time of the day at your place. First of all, find the latitude of your city with the help of an atlas. Cut out a triangular piece of cardboard such that its one angle is equal to the latitude of your place and the angle opposite to it is a right angle. Fix this piece, called gnomon, vertically along a diameter of a circular board a shown in Figure One way to fix the gnomon could be to make a groove along a diameter on the circular board.
Next, select an open space, which receives sunlight for most of the day. Mark a line on the ground along the North-South direction. Place the sundial in the sun as shown in Figure Mark the position of the tip of the shadow of the gnomon on the circular board as early in the day as possible, say 8:00 AM. Mark the position of the tip of the shadow every hour throughout the day. Draw lines to connect each point marked by you with the centre of the base of the gnomon as shown in Figure Extend the lines on the circular board up to its periphery. You can use this sundial to read the time of the day at your place. Remember that the gnomon should always be placed in the North-South direction as shown in Figure.
