Headings Forces and
Motion Search Questions 
To Calculate Speed or Velocity.
Either Speed or Velocity = Distance ÷ Time.
If an object
moving in a straight line
travels 25 metres in 5 seconds,
then its velocity = 25 ÷
5
= 5 m/s.
You must
always say what the units
are!
(in this case m/s, called "metres per
second").
Always check what units are given in the question.
If the time is given in hours or minutes,
then convert it to seconds before doing the calculation.
If an objects velocity does not
change, we say it has a constant
velocity.
In the above example,
we are not told whether the
object has a constant velocity,
or whether its velocity has
changed during the 5 seconds.
If the velocity has changed,
then the answer we have calculated is
an average velocity of 5 m/s.
If the velocity has not changed,
then the object had a constant velocity of 5 m/s.
When an objects velocity changes, it is called acceleration.
Headings Forces and
Motion Search Questions
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