Physics Final Exam: Kinematics, Newton's Laws, Energy, Gravity, Fluids, Heat, Electricity, Waves, Atomic & Nuclear, Projectiles & Orbits

Support force

Splits equally when weight is shared (ex: two bathroom scales = each reads half your weight).

Net force

The overall force and must include direction (ex: 20 N left - 15 N right = 5 N left).

Equilibrium

ΣF = 0; only applies to vectors because they have direction and can cancel.

Static equilibrium

Object is still.

Dynamic equilibrium

Object moves in a straight line at constant speed.

Acceleration

Cannot have constant velocity while accelerating.

Newton's First Law

Objects move straight unless a force changes their direction.

Newton's Second Law

Air resistance increases as speed increases.

Free fall

Accelerates at 10 m/s², so every second speed changes by ~10 m/s.

Terminal velocity

Heavier people reach higher terminal velocity (air resistance must grow to match their weight).

Newton's Third Law

Forces come in pairs: if you kick a ball with 1500 N, the ball pushes back on you with 1500 N.

Momentum

Is conserved.

Impulse

Impulse = force × time.

Work

Work = force × distance.

Power

Same work can be done slowly or fast; doing it faster = more power.

Efficiency

30% efficient machine → only 30% becomes useful work, 70% wasted.

Inverse-square law

If both masses double → force increases by 4×.

Pascal's Principle

Pressure in a fluid is transmitted equally.

Buoyancy

Floating in saltwater is easier because it has greater density → requires less displaced volume.

Specific Heat

Water has high specific heat, so it heats up slowly.

Electric Potential

Potential energy = joule; Electric potential (voltage) = volt.

Coulomb's Law

Double the distance → force becomes 1/4.

Transverse vibration

Perpendicular to wave motion.

Doppler Effect

Happens with sound & light.

Atomic number

= protons; = electrons in a neutral atom.

Half-life

After 2 half-lives → 1/4 of original remains.