Physics Final Exam Review Notes
DISPLACEMENT
- Displacement is a vector quantity that refers to an object's change in position.
- Represents the shortest distance from the initial to the final position.
MOTION AND MOTION GRAPHS
- Velocity is defined as:
\text{velocity} = \frac{\text{displacement}}{\text{time}} - The slope of a displacement-time graph indicates the velocity of the object.
2-D MOTION (PROJECTILES)
- For projectile motion:
- Horizontal acceleration (11x) is: \text{a}_x = 0 \, \text{m/s}^2
- Vertical acceleration (55y) is: \text{a}_y = -9.8 \, \text{m/s}^2
- Equations for projectile motion:
- Ax = V{0x}t
- Ay = V{0y}t + \frac{1}{2}a_y t^2
- Vy^2 = V{0y}^2 + 2ay(Ay)
FORCES
- In a free-body diagram, all forces acting on an object are represented as vectors with their respective magnitudes and directions.
- Equations of motion involving forces:
- When on an inclined plane:
F = uF_n - Normal force: F_n = m \cdot g \cos(\theta)
UNIVERSAL GRAVITATION
- All objects attract each other with a force proportional to the product of their masses and inversely proportional to the square of the distance between them:
F = G \cdot \frac{m1 m2}{r^2}
- Where G = 6.67 \times 10^{-11} \, \text{m}^2/\text{kg}^2
WORK AND ENERGY
- Work is calculated as:
W = \text{FORCE} \times \text{DISPLACEMENT} - Gravitational potential energy:
U_g = mgh - Kinetic energy:
KE = \frac{1}{2}mv^2 - Conservation of mechanical energy states:
U{initial} + K{initial} = U{final} + K{final}
MOMENTUM
- Momentum (p) is defined as:
p = mv \quad \text{(mass times velocity)} - Conservation of momentum:
P{initial} = P{final} - Two types of collisions:
- Elastic: Both momentum and kinetic energy are conserved.
- Inelastic: Only momentum is conserved; kinetic energy is not.
Buoyancy
- Buoyant force is the upward force exerted by a fluid, given by
Fb = \text{fluid density} \cdot g \cdot V{displaced}
WAVES AND SOUND
- The speed of a wave on a string is given by:
V = \sqrt{\frac{F}{\mu}}
Where F is tension and \mu is linear mass density. - Sound intensity and decibels relate as follows:
B = 10 \log{10}(\frac{I}{I0}) - Where I_0 = 1 \times 10^{-12} \text{W/m}^2
THERMODYNAMICS
- Heat transfer during a process is represented by:
Q = m \cdot c \cdot \Delta T - Ideal gas law represented as:
PV = nRT - Thermodynamic efficiency:
e = \frac{W{output}}{Q{input}}
- Where TC is the cold temperature and TH is the hot temperature.
- Work done by gas in thermodynamic processes is calculated as:
W = P \Delta V