Advertisements
Advertisements
Question
A cyclist travels a distance of 1 km in the first hour, 0.5 km in the second hour and 0.3 km in the third hour. Find the average speed of the cyclist in (1) km h-1, (2) m s-1.
Solution
Distance travelled in first hour = 1 km
Distance travelled in second hour = 0.5 km
Distance travelled in third hour = 0.3 km
Total time taken = 3 hr
Total distance travelled = 1 + 0.5 + 0.3 = 1.8 km
(1) Average speed in km h-1
Speed = `"Distance"/"Time taken"`
`=1.8/3 = 0.6 km h^-1`
(2) Average speed in m s-1
1 km = 1000 m
1.8 km = 1.8 × 1000 m
= 1800 m
1 hour = 3600 seconds
3 hour = 3600 × 3 = 10800 sec.
Average speed =`"D"/"T"`
=`1800/10800 = 0.167 "m s"^-1`
APPEARS IN
RELATED QUESTIONS
Define motion. What do you understand by the terms uniform motion and non-uniform motion ? Explain with examples.
Select the correct alternative
A car moving on a straight road is an example of
A boy goes from his house to school by bus at a speed of 20 km h-1 and returns back through the same route at a speed of 30 km h-1. The average speed of his journey is ______.
What is rotatory motion ? Give two examples.
How does a rotatory motion differ from the circular motion?
Identify the type of motion.
Movement of the earth around the sun:
Name the types of motion in which a body moves along a straight path
What type of motion do the following objects have?
Blade of an electric fan
What type of motion do the following objects have?
The smoke from a lighted dhoopbatti
Motion of a child on a swing is ______.
