Notes - Fisika - F2P Formulas

This document is written bilingually because it's primarily written for myself.

Chapter 1: Kinematika

1.1 Pengukuran

Angka Penting

Penjumlahan/Pengurangan: Ikut jumlah angka di belakang koma paling sedikit

Perkalian/Pembagian: Ikut jumlah angka penting paling sedikit

Pembacaan Alat Ukur

In cm, read the line before the 0 on the bottom markers, in this case 5.7

Then, add the line on the bottom markers, while paying attention to the scale, in this case 0.08

In total, it's 5.78

Sometimes there may be more markers at the bottom, which means you can be more precise with the measurements.

1.2 Jarak + Kelajuan vs. Perpindahan + Kecepatan

(v_t)=s/t

Distance/Jarak s (scalar) is how much is traveled.
In layman's terms, how much an object moves. That's why this is a scalar, because we only care about how much the object moves.
Speed/Kelajuan adalah (v_t)

v=Δ(s)/t

Displacement/Perpindahan Δ(s) (vector) is how much movement happened between 2 points.
In layman's terms, the difference between the starting and the end position. That's why this is a vector, as there is a direction and magnitude.
Velocity/Kecepatan adalah v

Note: For most if not all of this document, Δ(s) will be written as s, as most of the time they are the same value anyways.

1.3 Gerak Lurus

s=v*t

This has been mentioned in the previous subchapter.

s is distance

v is velocity

t is time

Always make sure all of the units are the same.

1.4 Gerak Lurus Berubah Beraturan (Acceleration/Deceleration)

a=Δ(v)/Δ(t)=((v_t)-(v_0))/t

(v_t)=a*t+(v_0)

This is the formula relating acceleration with the change of velocity. Think of acceleration as like the slope (gradient) of a line that graphs velocity.

Δ(v) is change in velocity

Δ(t) and t are time

(v_t) is velocity at time t

(v_0) is starting velocity

a is acceleration

s=t*(v_0)+(a*t2)/2

If you think of velocity as the y axis, and time being in the x axis, this formula makes even more sense. It's an integral (the area under a curve)!

s is distance

t is time

(v_0) is starting velocity

a is acceleration

(v_t)2=(v_0)2+2*a*s

This is for a more niche use case. Basically, given a certain distance, how much velocity will an object gain, given its acceleration?

(v_t) is velocity at time t

(v_0) is starting velocity

a is acceleration

s is distance

Note: Acceleration a can also be negative, to signify deceleration.

1.5 Gerak Vertikal

Given an object has no horizontal motion, calculating every component regarding the y axis should be trivial, knowing that gravity g has the units of acceleration. Most problems can be solved using GLBB. That's why I won't be repeating the same formulae again, rather displaying new ones that have specific use cases.

(h_max)=((v_0)2)/(2*g)

(t_(h_max))=(v_0)/g

These 2 formulae are for a specific use case. When giving a starting velocity upwards to an object, how can we find the peak height of the object, both in the time and space dimensions?

(h_max) is the maximum height

(v_0) is starting velocity

g is gravitational acceleration

(t_(h_max)) is time at maximum height

1.6 Gerak Parabola

(v_x)=(v_x(0))=(v_0)*cos(θ)

(v_y(t))=(v_0)*sin(θ)-g*t

Parabolic motion is easy. The x component is purely linear, while the y component is just vertical gravitational motion.

(v_x) is constant horizontal velocity

(v_y(t)) is vertical velocity, at some time t

θ is launch angle

g is gravitational acceleration

t is time

x=(v_x)*t

y=(v_y(0))*t-(g*t2)/2

Looks familiar? They are the same as GLBB and GLB.

x is relative coordinates in the x axis

y is relative coordinates in the y axis

(v_y(0)) is starting vertical velocity

g is gravitational acceleration

t is time

Now would be a good time to mention that in any parabolic motion problem you should be assuming the starting point as the cartesian origin (0,0). This makes things a whole lot easier for a lot of problems. For example, when throwing something off of a building, you can "extend" the y axis so that we accept negative y values, so the object has gone below the building's top.

(y_max)=((v_y(0))2)/(2*g)

(t_(y_max))=(v_y(0))/g

Looks familiar. This is how to find the peak.

(y_max) is maximum y

(t_(y_max)) is time to get to maximum y

(v_y(0)) is starting vertical velocity

g is gravitational acceleration

(x_max)=((v_0)2*sin(2*θ))/g=((v_0)2*2*sin(θ)*cos(θ))/g

(t_(x_max))=(2*(v_y(0)))/g=2*(t_(y_max))

I won't bore the reader with details. Just kidding, I will.

Given we are on flat ground, how can we find the maximum distance? These formulae are how.

(x_max) is maximum x

(v_0) is starting velocity

θ is launch angle

g is gravitational acceleration

(t_(y_max)) is time to get to maximum y

Remember that this is for flat ground only. If you're throwing something off a building or onto a building, you probably have to solve in 2 parts: The deceleration and acceleration part of the parabola.

1.7 Gerak Melingkar

v=ω*r

(a_c)=(v2)/r=ω2*r

T=(2*π)/ω

ƒ=1/T

This is rotational motion. It's easy if you remember the formulae.

The first formula is for linear velocity v . This is defined by multiplying angular velocity ω and the radius r .

Angular velocity is how many radians are traversed every second, or rad/s, while linear velocity is just regular old velocity. Remember that radians aren't "units" in the physics sense, so the end result doesn't have radians.

The second formula is for centripetal acceleration (a_c). It's what keeps the object from flying off into the distance.

The third formula is for the rotational period T , which is how much time it takes to complete a full rotation.

The fourth formula is for the rotational frequency ƒ , which is how much the object completes a full rotation within a specified time frame (unit).

Chapter 2: Dinamika

2.1 Hukum Newton

(∑_^)(F)=0

Newton's First Law: An object at rest stays at rest.

If there is no acceleration, the sum of all forces is 0

(∑_^)(F)=m*a

Newton's Second Law: The net force on an object is equal to the product of its mass and acceleration.

That's it. Force F is just mass m times the acceleration a

Newton's Third Law: For every action, there is an equal and opposite reaction. Forces always occur in pairs acting on different objects.

"Newton's third law. You gotta leave something behind."

There is always an opposite force. This is used mostly in inertial frame of references where nothing is moving, anyways.

All you remember is to always account for the N normal force and T tension of a rope.

Aplikasi: Gesekan (Friction)

ƒ=μ*N

Let's get into friction. Friction is derived from Newton's laws. Friction ƒ is defined by the friction coefficient μ times the normal force N

The normal force is basically how much force an immovable object is acting upon an object. This is always the same magnitude as how much the object is acting on the immovable object.

That's a very complicated explanation, but let's put it this way. The normal force acting upon an object is almost always the same magnitude or a component of the object's weight. On flat ground, an object weighs W newtons, therefore it needs N newtons of normal force in the opposite direction (up) so that the object doesn't move.

This also goes for diagonal surfaces, where only part of the weight W force is acting on the surface, therefore making the N normal force only part of the object's weight.

There's static friction (μ_s) and kinetic friction (μ_k). From their names you can probably guess that static friction is when the object isn't moving, while kinetic friction is when it is moving.

Always remember friction is applied last, as it is always opposite the direction of motion.

Aplikasi: Berat Semu (Dinamika Lift)

True weight is the gravitational force on an object (W=m*g). Apparent weight is the force an object exerts on its support, which is equal in magnitude to the normal force N acting on it. In an accelerating frame of reference like an elevator, the apparent weight can differ from the true weight.  

Applying Newton's Second Law in the vertical direction ((∑_^)((F_y))=N-m*g=m*(a_y))), the normal force (apparent weight) is N, where (a_y) is positive for upward acceleration and negative for downward acceleration.

2.2 MoPentum dan Jimpuls

p=m*v

Momentum p is the tendency for an object to stay along its current path through space. It is a vector. That's all you need to know.

J=F*Δ(t)=m*a*Δ(t)=m*Δ(v)=Δ(p)

Impulse is... I don't know. Impulse is change of momentum. Say you apply a force F for some amount of time Δ(t) you can then find the resulting momentum. Also, impulse is J for some reason.

If force F is acceleration, momentum p is the velocity, and impulse I is the displacement. Force changes momentum linearly and momentum changes impulse linearly. Whatever that means.

Kekekalan Momentum

(m_1)⋅(v_1)+(m_2)⋅(v_2)=(m_1)⋅(v_1^′)+(m_2)⋅(v_2)⋅(v_2^′)

Δ((v^′))/Δ(v)=-e

In any collision within an isolated system, the total momentum before the collision is equal to the total momentum after the collision. (p^_start)=(p_end)

There are 3 types of collisions:

1. Perfectly Elastic: Both momentum and kinetic energy are conserved. e=1

2. Perfectly Inelastic: Momentum is conserved, but kinetic energy loss is maximal, and the 2 objects stick together. (v_1^′)=(v_2^′) and e=0

3. Partially Elastic/Inelastic: 0<e<1

Oh, and PLEASE don't forget to have opposing signs when velocities are opposed to one another.

2.3 Dinamika Rotasi

τ=F*r*sin(θ)

Torsion τ is also called the moment of force. Basically, τ is rotational force; how effective is a force at rotating something?

r is the radius, the distance from the center of the object

sin(θ) is used because we only care about the perpendicular component of F. it is the angle between the force vector and the lever arm vector.

I=m*r2

The inertial moment I is the rotational version of mass. It's basically how hard it is to rotate an object.

m is the mass of the object

r is the radius of the object (or some other measure depending on the shape)

The main formula is for a point mass.

α=Δ(ω)/Δ(t)

τ=I*α

This is the F=m*a of rotational dynamics.

α is angular acceleration

(E_rot)=1/2*I*ω2

This is kinetic rotational energy.

ω is angular velocity

Chapter 3: Fluida

3.1 Fluida Statis

P=F/A

Start with the definition of pressure P.

Yeah, pressure P is equal to force F divided by the area A

This is chekhov's gun for fluid statics. This will suddenly appear in more complex problems.

Tekanan Hidrostatik

P=ρ*g*h

Quite simple. This is hydrostatic pressure.

P is pressure (Pa)

ρ is density

g is gravitational acceleration

h is depth

Principle: In a connected fluid that is at rest, the pressure at any two points on the same horizontal level is the same.

Remember that this is only hydrostatic pressure, which is the pressure worked on by the fluid. Remember to add atmospheric pressure (100000) when needed.

Prinsip Pascal

(F_1)/(A_1)=(F_2)/(A_2)

Pascal's Principle states that a change in pressure applied to an enclosed, incompressible fluid is transmitted undiminished to every portion of the fluid and to the walls of the containing vessel. This principle is the basis for hydraulic systems, which use fluid to multiply force.

F is the force applied

A is the area of the pull/pusher

Prinsip Archimedes

(F_a)=(W_fluid)=(m_fluid)⋅g=(ρ_fluid)⋅g⋅(V_submerged)

Archimedes' principle states that the buoyant force exerted on a body immersed in a fluid is equal to the weight of the fluid that hte body displaces. An object floats when its weight is exactly balanced on the buoyant force:

3.3 Fluida Dinamis

Q=A⋅v=V/t

Discharge/Debit Q is how much fluid flows for every unit of time.

A is area of cross section

v is velocity of fluid

V is volume

t is time

Kontinuitas Fluida

(A_1)⋅(v_1)=(A_2)⋅(v_2)

This is the fluid continuity equation. Discharge is always constant in a pipe with no leaks.

Persamaan Bernoulli

(P_1)+(ρ*(v_1)2)/2+ρ*g*(h_1)=(P_2)+(ρ*(v_2)2)/2+ρ*g*(h_2)=constant

Energy via pressure, via kinetic energy, and via potential energy is always c onstant in a moving fluid.

Δ(P)=1/2*(ρ_air)*((v_a)2-(v_b)2)

This is for planes. Also remember that F/A=P

Chapter 4: Gelombang Mekanik

A mechanical wave is a vibration that transfers energy through a material medium, such as a solid, liquid, or gas. Unlike electromagnetic waves, they cannot travel through a vacuum because they require particles to oscillate to propagate.

v=ƒ*λ

v is the wave's speed

ƒ is the wave's frequency

λ is the wavelength

4.1 Intensitas Bunyi dan Skala Desibel (dB)

I=P/A

Sound intensity (intensitas bunyi) I is a measure of the power of sound waves per unit area, typically measured in watts per square meter.

P is power

A is area

For example, for a speaker that sends out sound in all directions, the area is 4*π*r2

β=10⋅(log_10)(I/(I_0))

Because human ears hear logarithmically, we use the decibel scale (dB).

(I_0) is the reference sound intensity, 10(-12)

4.2 Efek Doppler

(ƒ_p)=(ƒ_s)⋅(v±(v_p))/(v∓(v_s))

(ƒ_s) is the original frequency

(v_p) is the speed of the receiver

(v_s) is the speed of the source

The top ± is positive if the receiver moves closer.

The bottom ∓ is negative if the source moves closer.

The general rule is that if the 2 objects move closer, the frequency gets higher.

4.3 Gelombang Berdiri

Gelombang pada Kawat/Dawai

L=n⋅(λ_n)/2

(ƒ_n)=v/(λ_n)

Gelombang berdiri terbentuk pada superposisi 2 gelombang yang identik yang bergerak pada arah berlawanan.

n refers to the nth harmonic. n=1 is the fundamental frequency (first harmonic). n>1 are called harmonics. The term overtone (nada atas) referes to any frequency higher than the fundamental, therefore the first overtone is n=2, the second n=3, and so on.

L is the length of the string/kawat/dawai

Resonansi pada Kolom Udara

Resonance occurs when a system is forced to vibrate at one of its natural frequencies, leading to a significant increase in amplitudes. In musical instruments like organ pipes, standing sound waves are produced in an air column. The boundary conditions determine the natural frequencies:

• An open end of a pipe is a displacement antinode (maximum air movement)

• A closed end of a pipe is a displacement node (no air movement)

These physical constraints lead to different sets if harmonics for open and closed pipes:

• Open pipe: (ƒ_n)=(n⋅v)/(2*L),k=n

• Closed pipe: (ƒ_n)=(n⋅v)/(4*L),k=(n+1)/2

To me, this sounds confusing. So let's use an example.

A closed pipe of length 15 has a standing wave with 3 nodes. This resonates with an open pipe that has 2 nodes. Find the length of the open pipe.

3⋅2=(n_1)+1

(n_1)=5

The closed pipe resonates at the 5harmonic.

(n_2)=2

Both of the frequencies must be the same.

(5⋅v)/(4⋅0.15)=(2⋅v)/(2⋅L)

L=4/5⋅15/100=0.12

It's that easy.

Chapter 5: Optik Fisik

5.1 Interferensi Gelombang: Lapisan Tipis

The vibrant colors seen on soap bubbles or oil slicks are a result of thin-film interference. This phenomenon occurs when light waves reflecting from the top and bottom surfaces of a thin film interfere with eachother. The resulting interference can be constructive (bright colors) or destructive (dark spots), and it depends on two main factors:

1. Path length difference: The wave reflecting from the bottom surface travels an extra distance, approximately 2*t, where t is the film's thickness.

2. Phase changes on reflection: A phase shift occurs when light reflects off a boundary with a medium of a higher refractive index.

Holy yap.

5.2 Dispersi Cahaya oleh Prisma

Dispersion is the separation of white light into its constituent spectrum of colors (ROYGBIV). This occurs because the refractive index of a material, like glass, is dependent on the wavelength of the light passing through it.

Enough yapping. What you need to know is this: The shorter the wavelength, the higher refractive index in glass, therefore the higher the deviation.

Red light has the longest wavelength, therefore red light undergoes the smallest deviation.

Violet light has the shortest wavelength, therefore violet light undergoes the greatest deviation.

5.3 Celah Ganda

y=(m*λ*L)/d

This is the equation for Young's double slit experiment.

y is distance from the center to the fringe

m is order number, 1, 2, 3, etc. for bright spots (constructive) and the space between (add half) for dark spots (destructive)

L is distance to screen

d is slit separation

5.4 Cermin dan Lensa

1/ƒ=1/(s_o)+1/(s_i)

M=(h_i)/(h_o)=-(s_i)/(s_o)=(s_i)/(s_o)

These are the primary equations for mirrors and lenses.

ƒ is focal l

(s_o) is object distance

(s_i) is image distance

(h_i) is image height

(h_o) is object height

M is magnification, use the second equation for mirrors and the third for lenses

Plus atau Minus?

Kacamata

D=1/ƒ

Diopters D measure the power of a lens. Use ƒ in meters.

5.5 Refraksi

TBW

Chapter 6: Panas dan Termodinamika

6.1 Kalorimetri

Q=m*c*Δ(T)

Q is how much energy (heat) it takes to change the temperature of a substance

c is the specific heat of the substance

Δ(T) is the temperature difference

That is literally all you need to know about this. Just kidding, there's 1 more thing.

Q=m⋅L

L is latent heat. Latent heat is basically how much energy it takes to go from 1 state of matter to another. Think of it as like paying an entry fare to a museum. For example, if you wanted to make 0 water, you'd first have to calculate the Q for getting the ice to that temperature, then add the Q to change the phase from solid to liquid.

Azas Black

(Q_lepas)=(Q_terima)

Black's Principle states that when two bodies at different temperatures are mixed or in thermal contact, the heat lost by the hotter body equals the heat gained by the colder body (if no heat is lost to the surroundings).

Energy is conserved — heat flows from hot to cold until both reach the same final temperature.

6.2 Perpindahan Panas

Heat is transferred by 3 mechanisms:

1. Conduction: DIrect contact

2. Convection: Movement of fluids (a medium)

3. Radiation: Electromagnetic waves.

A thermos is designed to minimize all three mechanisms of heat transfer:

1. Double-walled chamber with vacuum: If there's no material to conduct, then there's no conduction or convection

2. Silvered surfaces: Reflective layers minimize thermal radiation.

3. Stopper/Lid: Minimizes heat transfer by preventing convection and limiting conduction.

6.3 Efek Rumah Kaca

Can you tell I'm just adding material off of the tryouts?

You should already know that the greenhouse effect is basically trapping heat and light in the atmosphere, therefore heating up the atmosphere.

Here are the materials that contribute to the greenhouse effect:

1. Carbon Dioxide (CO2): Burning fossil fuels

2. Methane (CH4): Livestock farming and natural gas leaks

3. Nitrous Oxide (N2O): Nitrogen-based fertilizers

4. Chlorofluorocarbons (CFCs): Aerosol sprays, refrigerants.

6.4 Teori Kinetik Gas

EK=3/2*n*R*T

The kinetic theory of gases models a gas as a large number of randomly moving particles. THAT and the equation is all you need to know.

You probably don't need to use the equation directly, just using its proportionality.

n is number of things, in moles

R is 0.082

T is temperature

6.5 Hukum Termodinamika 1

Δ(U)=Q-W

The First Law of Thermodynamics is a statement of the conservation of energy: the change in a system's internal energy Δ(U) is equal to the heat added to the system Q minus the work done by the system W.

6.6 Hukum Termodinamika 2

η=1-(T_L)/(T_H)

The Second Law of Thermodynamics states that heat flows spontaneously from a hotter body to a colder one, and that it is impossible for any cyclic process to convert heat entirely into work.

The Carnot cycle is a theoretical, reversible thermodynamic cycle consisting of two isothermal and two adiabatic processes. It represents the most efficient possible heat engine operating between two temperature reservoirs.

The efficiency of any heat engine is the ratio of the work done W to the heat absorbed from the hot reservoir (Q_H).

6.7 Pemuaian

TBW

Chapter 7: Listrik dan Kemagnetan

7.1 Listrik Statik

Hukum Coulomb

F=k⋅|(q_1)⋅(q_2)|/(r2)

Coulomb's law describes electrostatic force F between two stationary point charges (q_1) and (q_2) separated by a distance r. The force is a vector: it is repulsive for like charges and attractive for opposite charges, acting along the line connecting them.

k=9.0⋅109

Medan Listrik dan Potensial Listrik

E=(k*q)/(r2)

V=E*r

The electric field E is a force per unit charge at a point in space, created by a source charge q. It is a vector quantity.

The electric potential V is the electric potential per unit of charge. It is a scalar quantity.

7.2 Listrik Dinamis

V=I*R

V is voltage

I is current

R is resistance

The behavior of current, voltage, and resistance differs fundamentally in series and parallel circuits.

Menyelesaikan Masalah Rangkaian

TBW

7.3 Daya Listrik dan Energi Listrik

P=I*V=I2*R=(V2)/R

E=P*t

Power P is the rate at which electrical energy is consumed or converted. It is measured in watts (W).

Electrical energy E is the total work done or heat generated by a circuit over a period of time t. It is measured in joules (J).

Q=E=P⋅t=I2*R

There is also Joule's law, which states that when an electric current I passes through a resistor R for some time t, the electrical energy converted to heat is given by the equation above. This principle demonstrates the conservation of energy, where electrical energy is transformed into thermal energy.