Basic Physics B571B0

1. **Newton's Three Laws:** 1. An object remains at rest or in uniform motion unless acted upon by a net external force: $$\vec{F}_{\text{net}} = 0 \Rightarrow \text{constant velocity}$$. 2. The net force on an object is equal to its mass times its acceleration: $$\vec{F}_{\text{net}} = m\vec{a}$$. 3. For every action, there is an equal and opposite reaction: $$\vec{F}_{12} = -\vec{F}_{21}$$. 2. **The Kinematic Equations (for constant acceleration):** - $$v = v_0 + at$$ - $$x = x_0 + v_0 t + \frac{1}{2}at^2$$ - $$v^2 = v_0^2 + 2a(x - x_0)$$ 3. **Conservation of Energy:** - Total mechanical energy is conserved if only conservative forces act: $$E_{\text{total}} = K + U = \text{constant}$$ - Kinetic energy: $$K = \frac{1}{2}mv^2$$ - Potential energy (gravitational): $$U = mgh$$ 4. **Conservation of Momentum:** - Total momentum before and after an interaction is conserved if no external forces act: $$\vec{p}_{\text{initial}} = \vec{p}_{\text{final}}$$ - Momentum: $$\vec{p} = m\vec{v}$$ 5. **Coulomb's Law:** - The force between two point charges: $$F = k_e \frac{|q_1 q_2|}{r^2}$$ - Where $$k_e = 8.99 \times 10^9 \text{ N m}^2/\text{C}^2$$ 6. **Ohm's Law:** - The current through a conductor between two points is directly proportional to the voltage across the two points: $$V = IR$$ - Where $$V$$ is voltage, $$I$$ is current, and $$R$$ is resistance. These are fundamental physics principles and equations to memorize for basic physics understanding.