This is the link of previous exercise http://seekhe.com/school/ncert-class-9th-physics-science-chapter-1-motion-solutions-exercise-9-1/
In this post you will get solutions of NCERT Class 9th Physics Chapter 1 Motion Exercise1. 2
It covers the questions of topic velocity, speed, average speed and velocity.
Que1: what is difference between speed and velocity.
The speed is ratio of distance to time which is useful to determine the length of path covered in that given interval of time but velocity is ratio of displacement to time it have direction too speed can be positive zero but not negative but velocity can be positive negative and zero. it is a vector quantity.
Que2:under what conditions the average speed will be equal to average velocity.
The speed is given by ratio of distance to time whether the velocity is given by displacement to time when distance travelled by object becomes equal to displacement of object the average speed becomes equal to average velocity.
Que3:what does an odometer of automobile measures.
The odometer measures the speed i.e.
Distance covered by an object.
Que4:what does the path of object look like when it is in uniform motion.
The path will be straight line when an object is in uniform motion.
Que5: during an experiment a signal
From spaceship reached the ground
Station in five minutes
What was the distance of space ship from ground station. The signal travels at speed of light.
The signal took five minutes to cover distance ‘x’
Now speed = distance /time
Speed*time = time
Given : speed = 3*10^8
Time = 5 minutes = 300 sece
Distance ‘x’ = 3*10^8*300
= 900 *10^8 meter.
