In this post we have covered complete solutions of class 9th physics chapter 1 – motion exercise 1.1 solutions with questions. You can get complete chapter wise solutions from here – All Chapter Solutions
NCERT Class 9th Physics ( Science ) Chapter 1 – Motion Solutions ( Exercise 8.1 )
Below questions covers following topics –
- 8.1 Describing Motion
- 8.1.1 Motion Along A Straight Line
You can further read the summary and notes from here
Question 1: An object move through distance can it have zero displacement?
If yes support your answer through an example.
Ans 1: Yes it can have zero displacement because displacement is measure of of length from mean position to present position while distance us measure of the total length an object travels
For example there are two points A and B two meter apart now if a boy is in point and he first goes A to B then comes back to A then displacement will be zero because he is in his mean position but distance will be 4m because he first covered 2m while going from A to B then from B to A
Question 2: A farmer moves along the boundary of square field of side 10m in 40sec what will be the magnitude of displacement at the end of 2min 20sec.
Ans: The farmer moves along the boundary of field in 40sec
So the distance covered by him will be = 4*10= 40m
The distance covered by him in 2min 20 sec will be = 40/40*140
= 140m
Now 140/40= 3.5 rounds of field so there will be two cases
If he start from center of side his 3.5 round will end on the middle of side just parallel to the side he was previously before starting so the displacement will be 10m
If he starts from the corner of the field his 3.5 round will end in diagonally opposite corner so his displacement will be = (10²+10²)½
= 14.14 m
Question 3: which of the following is true for displacement
a) it cannot be zero
b) its magnitude is greater than distance travelled by an object.
Ans:
a) not true because displacement can be zero if starting position and ending position is same.
b) not true
Because displacement is shortest measurable length between the mean position to end position but distance is measure of total length traveled by an object.
We have provided the Solutions of 9th Class Physics as well, please check at below link –
Tags: 9th class physics solutions, exercise 8.1 solutions, motion chapter solution,class 9th science summary, ncert 9th class physics notes, 9th class physics solutions, physics notes, physics, cbse physics solutions, exercise 8.1 physics 9th class
