19. If you solved for the distance
travelled by each participant
over the time he took to cover
such distance, then you have
computed for his average
speed. But why average speed
and not just speed?
20. It is considered average
speed because it
represents the speed of
the participant throughout
his travel.
21. During his travel, there
were instants that his
speed would vary. His
speed at an instant is
called instantaneous
speed .
22. Similarly, the velocity of a
moving body at an instant is
called instantaneous
velocity. The instantaneous
speed may be equal, greater
than, or less than the
average speed.
23. When an object’s
instantaneous speed values
are always the same, then it
means that the object is
moving with constant speed.
We refer to this as constant
motion.
24. Where you will be and
what time you will reach
your destination is easily
predicted when you move
at constant speed or
velocity.
28. Acceleration is introduced as
due to the change in the
speed of the moving object.
It may also be due to the
change in the direction of
the object.
30. Let us summarize what you
have learned by relating
distance , displacement,
speed, velocity, and
acceleration.
31. If an object does not
change its position at a
given time interval, then
it is at rest or its speed is
zero or not accelerating.
32. If an object covers equal
distance at equal intervals
of time, then it is moving
at constant speed and still
not accelerating.
33. If an object covers varying
distances at equal intervals
of time, then it is moving
with changing speed or
velocity. It means that
the object is accelerating.