شرح ساينس الصف الثاني الاعدادي لغات
شرح ساينس تانية اعدادي

لينك تحميل الملزمة
https://drive.google.com/file/d/1guFZFe2N5QKd3M1dHBqR0ZCqUBgkI9k3/view?usp=sharing

لينك تليجرام
https://t.me/mrahmedelbashagroup

In This Video :
G.R
• Hearing thunder after seeing lightning although they both happen at the same time.
Because the light of lightning is from electromagnetic waves, while the sound of thunder is mechanical waves, where the velocity of electromagnetic waves is much greater than the velocity of mechanical waves.

• We can't hear the sound of solar explosions occurring on the Sun, but we can see the light coming out of it.
Because the sound is mechanical waves, which need a medium to propagate through, while the light is electromagnetic waves, which can propagate through vacuum.
Wave amplitude:
It is the maximum displacement achieved by the medium particles away from their rest positions.
•The measuring unit of wave amplitude is "meter".
Law used for determination the wave amplitude:


بالتوفيق
مستر احمد الباشا