Page 4 - Science E-Book Prep.3 2024-2025 1st term unit1_Neat

Science Department
Prep.3

Unit one:

Lesson 1: "Motion in one direction"

Motion:
The change of an object’s position as time passes according to the
position of another object.

*The simplest type of motion is the motion in one direction, such as the
movement of the train which moves forwards or backwards but it doesn’t
move upwards or downwards. If the path of the train is straight so the
movement of it will be straight line in one direction motion.

- Speed is the physical quantity that distinguishes the description of
objects either fast or slow.

There are two factors necessary to describe the movement:

Distance Time

So, speed is:

The distance covered in a unit time.

If an object covers a distance (?d) with a short time (?t),
then the speed of this object (V) is:

Measuring units: meter/ second (or km /hour)

First Term 4