proton (质子) neutron (中子) electron (电子) Name Charge Mass Location Role Proton +1 $1$ Inside Nucleus Determine the identity Neutron 0 $1$ Inside Nucle

W = \Delta E = F \cdot d Types of energy Gravitational Potential Energy GPE = mgh Kinetic Energy K_{E} = \frac{1}{2}mv^2 Conservation of Energy [!def]

[!important] An object in circular motion is constantly changing velocity direction It’s resultant force is towards the circle center Centripetal Forc

Momentum p = m \cdot v \text{momentum} = \text{mass} \cdot \text{velocity} [!def] quantity possessed by masses in motion measure of how difficult it i

[!def] Friction is the force that opposes motion between any surfaces that are in contact Static (Starting) Friction [!def] Static friction is the for

Gravity g [!sticky | red s-90] Gravity is not a force, but a acceleration [!sticky | aqua s-90] Gravitational Force is a force. [!def] acceleration -

Speed and Velocity Speed: does not depend on direction Velocity: the speed and direction. Calculating Write this: \text{speed} = \frac{distance}{time}

Mass and Weight Mass Mass and weight are not the same Mass is the amount of matter in an object and is measured in kilograms Mass has the same value e

Measurement instrument -> decimal point -> accuracy, not s.n. calculation -> significant figures -> the same as before to avoid parallax(视差) error rea

$$\text{Moment} = \text{Force} \times \text{Perpendicular distance from the pivot}$$ $$\boldsymbol{M} = \boldsymbol{F} \times \boldsymbol{v}$$ $$\sum