شرح ساينس الصف الخامس الابتدائي لغات مستر احمد الباشا
ساينس خامسة ابتدائي

لينك تحميل الملزمة
https://drive.google.com/file/d/1tMZdXRrqVJRWc0zni5UnzWs_MLBpsyDR/view?usp=sharing

لينك تليجرام
https://t.me/mrahmedelbashagroup

In this part :
Activity: To investigate the effect of gravity and air resistance on different
objects.
Tools:

Steps:
1. Stand on a chair and drop the two balls at the same time from the same height, then observe which ball will reach the floor first.

Observation:
The metal ball will reach the floor first.

2. Stand on a chair and drop the paper clip and the feather at the same time from
the same height, then observe which one will reach the floor first.

Observation:
The paper clip will reach the floor first.

Conclusions:
1. The plastic ball with holes took longer time to reach the floor, because it was
slowed by upward-flowing air more than the metal ball.
2. The feather took longer time to reach the floor, due to its shape as the feather
is affected by air resistance more than the paper clip.
- So that, air resistance is a factor that can slow down the falling objects.

Law of Motion
The force of gravity is constant and acts on all objects in the same way.

Imagine that there is no air resistance on Earth:
So, according to the Law of Motion, if we drop a hammer and a paper at the same
time from the same height, they will reach the floor at the same moment because
gravity acts on all objects in the same way, where the mass or the shape of the
objects would not matter.

► Our solar system consists of the Sun and a group of planets revolve around it.
► In 1543, a scientist called Nicolaus Copernicus stated that Earth revolves around the Sun.
► In the solar system, each planet revolves around the Sun in a fixed path called an orbit.
► The orbit of each planet has an ellipse (oval) shape.
► Earth revolves around the Sun at a speed nearly equals 107000 km per hour.

But, what keeps the planets revolve around the Sun in fixed orbits?
► Gravity is the invisible attraction or pulling force that holds all the planets in their places.
► The great gravitational pulling force of the Sun keeps the planets revolving in fixed orbits.
► If there were no gravity, the planets would fly off into space.


بالتوفيق
مستر احمد الباشا