Audio Podcast Quiz 1: Fullscreen Mode Quiz 2: Fullscreen Mode Other note 1 source Other note 2 source 5.2.1 Detection of radioactivity ## Radioactivity Detection Radioactivity is the process of releasing radiation from an unstable atomic nucleus. We are all exposed to radiation from various sources every day. Let's discuss some important things about radioactivity: ## Background Radiation Sources Background radiation comes from a variety of sources, both natural and artificial: - Cosmic rays from the sun - Radon gas in the air - Radon-containing granite rocks - Potassium-40 in food - Medical procedures that use radioisotopes - Nuclear power plants and the rest of the nuclear bomb tests ## Ionization Effect Radiation can cause ionization, which is the process of releasing electrons from atoms or molecules. This can be evidenced by: Electroscope Experiments: - When a fire or radium source is brought close to a charged electroscope, the charge is los...
Quiz 1: Fullscreen Mode Theory of Moments Theory of Moments What is a Moment? The moment of a force is the turning effect produced by a force acting at a distance from a pivot or fulcrum. It depends on: The magnitude of the force (\(F\)) The perpendicular distance (\(d\)) from the line of action of the force to the pivot The formula for calculating the moment is: Moment (\(M\)) = Force (\(F\)) × Perpendicular Distance (\(d\)) Unit: Newton meter (Nm) Law of Moments The law of moments states that for a system in equilibrium: Sum of Clockwise Moments = Sum of Anticlockwise Moments This means there is no net turning effect on the body. Conditions for Equilibrium A body is in equilibrium when: The sum of all forces acting on it is zero (no net force). The sum of all moments about any point is zero (no net moment). Examples and Applications Example 1: Balanci...
Quiz 1 Fullscreen Mode Trigonometri: Aturan Sin, Cos, dan Luas Segitiga Trigonometri: Aturan Sin, Cos, dan Luas Segitiga 1. Aturan Sinus Aturan sinus digunakan untuk menghitung sisi atau sudut dalam segitiga, dengan syarat terdapat minimal satu pasang sisi dan sudut yang berhadapan. Rumus: \[ \frac{a}{\sin A} = \frac{b}{\sin B} = \frac{c}{\sin C} \] Contoh: Diketahui ∆ABC dengan BC = 10 cm, AC = 20 cm, dan ∠BAC = 30°. Hitunglah ∠BCA. Solusi: \[ \frac{\sin B}{b} = \frac{\sin A}{a} \] \[ \sin B = \frac{20 \cdot \sin 30°}{10} = 1 \] Maka ∠BCA = 60°. 2. Aturan Cosinus Aturan cosinus digunakan untuk menghitung sisi atau sudut, terutama ketika diketahui dua sisi dan sudut di antaranya, atau semua sisi segitiga. Rumus: \[ a^2 = b^2 + c^2 - 2bc \cdot \cos A \] \[ b^2 = a^2 + c^2 - 2ac \cdot \cos B \] ...