ASB 2023 G11 Physics C Review

Reference Frames & Displacement
- A reference frame is needed to measure position, distance, or speed.
- Displacement is the change in an object's position from its starting point.
- It's a vector quantity, possessing both magnitude and direction.
Average Velocity
- Average speed = total distance / total time
- Average velocity = displacement / time
- Velocity is a vector, having both magnitude and direction.
Instantaneous Velocity
- Average velocity over an infinitesimally short time interval.
Acceleration
- Change in velocity/time taken to change velocity.
- Acceleration is a vector, having both magnitude and direction.
- Positive/negative values depend on direction of change.
Motion at Constant Acceleration
- Equations for constant acceleration motion.

Vector and Scalars
- Vectors have both magnitude and direction.
- Scalars are completely described by a magnitude.
Addition of Vectors
- Component Method: Vectors can be broken down into components along different axes.
- Graphical Method: Use of drawings/diagrams to add vectors

Horizontal component of motion
- Horizontal motion at a constant velocity.
- Time of flight = (2 x Vertical Initial velocity) / (gravity)
Vertical component of motion
- Vertical motion affected by gravity
- Time of flight = Vertical final velocity / gravity

Force
- Force is a pushing or pulling action that can change an object's state of motion.
Newton's First Law of Motion (Law of Inertia)
- An object in motion will stay in motion unless acted upon by an unbalanced force.
Newton's Second Law of Motion
- Acceleration of an object is directly proportional to the net force acting on it, and inversely proportional to its mass. This relationship follows the equation F = ma.
Newton's Third Law of Motion
- For every action, there is an equal and opposite reaction.
Mass
- A measure of inertia.

Work done by a Constant Force
- Work is calculated as the product of force and displacement in the direction of the force. It's expressed by the equation W=Fdcosθ, where F is the force, d is the displacement, and θ is the angle between the force and displacement vectors.
Work Done by a Varying Force
- Work is the integral of force with respect to displacement. It's the area under the force-displacement curve.

An object falling through a fluid (a liquid or gas) will eventually reach a constant velocity, terminal speed.
Terminal speed occurs when the drag force equals the gravitational force.
The formula for terminal speed is VT = mg/k where m is the mass of the object and k is a constant based on the fluid, object size and shape.

Kinetic energy (KE): The energy an object possesses due to its motion. It's calculated using the equation KE = 1/2mv².
Work-Energy Principle: The net work done on an object equals its change in kinetic energy.

Potential energy (PE): The energy stored in a body due to its position.
Gravitational potential energy (GPE): The energy an object has due to its position relative to a reference point in a gravitational field. It's calculated using the equation PE = mgh, with m being mass, g being gravity, and h being height.
Elastic potential energy (EPE): The energy stored in a deformed elastic object. It's calculated from Hooke's Law, EPE = ½kx².
Conservative/Nonconservative forces: forces that are path-independent/dependent on the path, respectively.

Kinematics of uniform circular motion
- Uniform circular motion involves an object traveling at a constant velocity along a curved path. (e.g. a ball on a string)
Torque
- Torque is a rotational force, which can cause a change in an object's rotational state.
Rotational Kinetic Energy
Angular Momentum, Angular Momentum Conservation
Angular Momentum
- Angular Momentum is calculated by L = Iω.

Momentum
- Momentum is a vector quantity.
Impulse
- The change in momentum of an object is equal to the impulse exerted on it.
Elastic collisions
- Momentum and kinetic energy are both conserved.
Inelastic collisions
- Momentum is conserved but kinetic energy is lost.

Angular quantities are related to the rotational motion of objects.
Torque (τ) is the rotational analog of force;
Rotational Inertia (I) describes the resistance of an object to changes in its rotational motion.
Relationships between linear and angular quantities exist.

Simple Harmonic Motion (SHM): A special type of periodic motion where the restoring force is directly proportional to the displacement from equilibrium.
Examples of SHM include springs or pendulums involved in oscillatory motion.
Energy considerations for SHM.

Simple Harmonic Motion (SHM): A special type of periodic motion where the restoring force is directly proportional to the displacement from equilibrium.
Energy Considerations in SHM.

Kepler's Laws summarize observations of planetary orbits.
Newton's Laws of Motion and Universal Gravitation give a more general understanding.
Gravity plays a significant role in orbital mechanics.

Important considerations in gravitational potential energy are mass , location relative to a center of mass, and the amount of work that must be done to move an object.
Escape velocity is the minimum velocity required for an object to escape from the gravitational pull of a planet or other celestial body.