1. Why do we need to measure time?
2. What is a sundial?
3. Define speed. Write its SI unit.
4. How are distance, time and speed of a moving
object related to each other?
F. Answer these questions.
Answers
Answer:
Answer1. All our activities depend on time. ... For example, to know the duration of a journey, to meet the schedules in work, to know whether its day or night, to know the heartbeat, to know the amount of time taken by the computer to perform an operation etc. Hence it is very important to measure the time.
Answer2. A type of clock used in past times that uses the dark shape (shadow) caused by a pointed piece of metal being between the sun and the clock surface to show what the time is
Answer3. Speed is defined as the rate of change of distance with time. It has the dimension of distance by time. Thus, the SI unit of speed is given as the combination of the basic unit of distance and the basic unit of Time. Thus, the SI unit of Speed is meter per second.
Answer4. The distance travelled by an object from intial point to final point is called distance and in which velocity we are travelling is called speed and the time taken to travel from one place to another is called time. In this way distance,time,and speed is inter related to each other.
Answer:
Ans- Speed is a measurement of how fast an object moves relative to a reference point.
Speed can be calculated by the formula:
Speed = Distance/Time
or
s = d/t
SI Unit of speed is meter per second
Other units of speed such as kilometers per hour, meters per second, feet per second, miles per hour etc.
Explanation: