Question
By giving one example each, define
1. variable velocity.
2. average velocity.
3. uniform velocity.
1. variable velocity.
2. average velocity.
3. uniform velocity.
✓
Answer
(i) Variable velocity: When a body covers unequal distances in equal intervals of time in a specified direction, the body is said to be moving with a variable velocity.
Example: A rotating fan at a constant speed has variable velocity, because of continuous change in direction.
(ii) Average velocity: The ratio of the total distance travelled in a specified direction to the total time taken by the body to travel the distance is called average velocity.
Example: If you walk to a campsite 1 km away and then back to your starting point with in 1 hour, then your average velocity will be zero because your initial and final position is same.
(iii) Uniform velocity: When a body covers equal distances in equal intervals of time
(however small may be the time interval) in a specified direction, the body is laid to be moving with uniform velocity.
Example: A car moving on a straight road with constant speed has uniform velocity.
Example: A rotating fan at a constant speed has variable velocity, because of continuous change in direction.
(ii) Average velocity: The ratio of the total distance travelled in a specified direction to the total time taken by the body to travel the distance is called average velocity.
Example: If you walk to a campsite 1 km away and then back to your starting point with in 1 hour, then your average velocity will be zero because your initial and final position is same.
(iii) Uniform velocity: When a body covers equal distances in equal intervals of time
(however small may be the time interval) in a specified direction, the body is laid to be moving with uniform velocity.
Example: A car moving on a straight road with constant speed has uniform velocity.
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