Question

Distinguish between speed and velocity.

NCERT Class IX
Sciences - Main Course Book

Chapter 8. Motion

Answer 1

Speed-
Speed is the rate at which an object covers distance in a particular time.
It is a scalar quantity.
Formula:-  speed=Distance/time
Speed depends upon the distance traveled.

Velocity-
Velocity is the displacement traveled by a body per unit time.
It is a vector quantity.
Formula:-  velocity=Displacement/time
Velocity depends upon the displacement traveled by a body.
Velocity can be 0.

Answer 2

"Speed:

• Speed refers to the "rate of change" of distance with "respect to time".
• It is a "scalar quantity".
• It does not indicate the direction in which the object is moving.
• $Speed =\frac{\text { Distance }}{\text { Time }}$

Velocity:

• Velocity refers to the "rate of change of displacement" with "respect to time".
• It is a "vector quantity".
• It indicates the direction in which the "object is moving".
• $Velocity =\frac{\text {Displacement}}{\text { Time }}$"