Scrap Mechanic

Scrap Mechanic

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Physics Formulas (Speed, Distance, Time, etc)
By Piano Man
Formulas
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Formulas
I = m × r2 --Inertia Formula (I = m × (r × r) M = mass, r = width/diamiter

Distance / Time = Speed

Distance / Avg. Time = Avg Speed

(Final Speed - Initial Speed) / Time = Avg. Acceleration

Gravitational acceleration = 39.24 blocks/s/s

Hovering

Force to maintain a hover = (Mass * 0.2616) / number of thrusters
(Note, make sure that the average of the position of the thrusters is in line with the centre of mass, and that the distance between the centre of mass and each thruster is the same)

Force to maintain a hover with angled thruster = (Mass * 0.2616) / (cos(angle) * number of thrusters)

Slope = Rise/Run .... (speed/or/acceleration/or/distance)/Time

Formulas Horse-Power = 1.225*(number of blocks(meters) in front)*()*velocity^3
The horsepower needed to overcome aerodynamic drag at a given speed is: HP = k*A*Cd*v^3 Density of air = 1.225 kg/m³
Where HP is horsepower, k is the density of air, A the frontal (cross-sectional) area, Cd the coefficient of drag, and v the velocity. The density of air depends on conditions but is nominally .08 lb/ft^3.

Aerodynamic drag is calculated as: F = 1/2 CDAV^2
Where: F - Aerodynamic drag force, Cd - Coefficient of drag, D - Density of air (nominally about 0.08 pounds per cubic foot.. yes I know that's not a technically accurate mass but it saves converting to and then back from metric), A - Frontal area, V - Velocity of object

To estimate engine HP from 1/4 mile run: HP = ((trapspeed/234)^3) * weight

Tire Diameter in inches = ( ( Tire Width * Aspect Ratio ) / 25.4 ) * 2 + Wheel Diameter
Example: 245/40-17 would be ( ( 245 * .40 ) / 25.4 ) * 2 ) + 17 = 24.71653543307

MPH = ( RPM * Tire Diameter ) / ( ( gear ratio * final drive ) * 336 )
Example: ( 8000 * 24.71653543307 ) / ( ( .771 * 4.062 ) * 336 ) = 187.9074535627 MPH
Of course the tires expand at high speeds so this isn't totally accurate.

DRAG = FD = ρ*v2*CD*A/2

To find Drag Coefficent solve; formula for angular velocity is ω = (θf - θi) / t Key = ω = angular velocity θf = the final angle θi = the initial angle t = time

angle of attack formula = atan(velocity along yaw axis/velocity along roll axis)= (answer)
1=
CD ≈ 0.01*θ
where θ is the angle of attack of the object in radians. What I don't like about this formula is the "≈" sign, and so I avoid using it completely. to convert degrees to radians use "(degrees)/57.2957795"
2=

CD = (2*FD)/(ρ*v2*A)
where ρ is the density of the fluid the object is travelling in, v is the velocity of the object, CD is the drag coefficient of the object and A is the surface area of the object.

Reference: https://www.physicsforums.com/threads/how-to-calculate-drag-coefficient.667709/


Any object moving through a fluid experiences drag - the net force in the direction of flow due to pressure and shear stress forces on the surface of the object.

The drag force can be expressed as:

Fd = cd 1/2 ρ v2 A (1)

where

Fd = drag force (N)

cd = drag coefficient

ρ = density of fluid (1.2 kg/m3 for air at NTP)

v = flow velocity (m/s)

A = characteristic frontal area of the body (m2)

The drag coefficient is a function of several parameters like shape of the body, Reynolds Number for the flow, Froude number, Mach Number and Roughness of the Surface.

The characteristic frontal area - A - depends on the body.

Objects drag coefficients are mostly results of experiments. The drag coefficients for some common bodies are indicated below:

Type of Object, Drag Coefficient
- cd - Frontal Area
Laminar flat plate (Re=106) 0.001
Dolphin 0.0036 wetted area
Turbulent flat plate (Re=106) 0.005
Subsonic Transport Aircraft 0.012
Supersonic Fighter,M=2.5 0.016
Streamlined body 0.04 π / 4 d2

Airplane wing, normal position 0.05 WING DRAG COEFFICENT

Sreamlined half-body 0.09
Long stream-lined body 0.1
Bicycle - Streamlined Velomobile 0.12 5 ft2 (0.47 m2)
Airplane wing, stalled 0.15
Modern car like a Tesla model 3 or model Y 0.23
Toyota Prius, Tesla model S 0.24 frontal area
Tesla model X
Sports car, sloping rear 0.2 - 0.3 frontal area
Common car like Opel Vectra (class C) 0.29 frontal area
Hollow semi-sphere facing stream 0.38
Bird 0.4 frontal area
Solid Hemisphere 0.42 π / 4 d2
Sphere 0.5
Saloon Car, stepped rear 0.4 - 0.5 frontal area
Bike - Drafting behind an other cyclist 0.5 3.9 ft2 (0.36 m2)
Convertible, open top 0.6 - 0.7 frontal area
Bus 0.6 - 0.8 frontal area
Old Car like a T-ford 0.7 - 0.9 frontal area
Cube 0.8 s2
Bike - Racing 0.88 3.9 ft2 (0.36 m2)
Bicycle 0.9
Tractor Trailed Truck 0.96 frontal area
Truck 0.8 - 1.0 frontal area
Person standing 1.0 – 1.3
Bike - Upright Commuter 1.1 5.5 ft2 (0.51 m2)
Thin Disk 1.1 π / 4 d2
Solid Hemisphere flow normal to flat side 1.17 π / 4 d2
Squared flat plate at 90 deg 1.17
Wires and cables 1.0 - 1.3
Person (upright position) 1.0 - 1.3
Hollow semi-cylinder opposite stream 1.2
Ski jumper 1.2 - 1.3
Hollow semi-sphere opposite stream 1.42
Passenger Train 1.8 frontal area
Motorcycle and rider 1.8 frontal area
Long flat plate at 90 deg 1.98
Rectangular box 2.1











θ = angle of attack in radians


angle of attack formula is: atan(velocity along yaw axis/velocity along roll axis) = (answer)


to convert degrees to radians use "(degrees/answer)/57.2957795"


formula for angular velocity is ω = (θf - θi) / t Key = ω = angular velocity θf = the final angle θi = the initial angle t = time


Key = ω = angular velocity θf = the final angle θi = the initial angle t = time


t get time use formula Distance/Speed = Time


* coefficent of drag(CD) formula:





CD ≈ 0.01*θ








Overall the HorsePower needed to overpower aerodynamic drag is CoDr = Coeffectiant of Drag * or Codr = 0.01*(atan( ( (360 - 0) / (Distance/Speed) ) / ( (360 - 0) / (Distance/Speed) ) ))/57.2957795
(







Horse-Power = 1.225*(number of blocks(meters) in front)*(CoDr)*velocity^3





full formula is:

Horse-Power = 1.225*(number of blocks(meters) in front)*(0.01*(atan( ( (360 - 0) / (Distance/Speed) ) / ( (360 - 0) / (Distance/Speed) ) ))/57.2957795)*velocity^3


Formulas 2
D = .5 * Cd * r * V^2 * A

The drag equation states that drag (D)is equal to a drag coefficient (Cd) times the density of the air (r) times half of the square of the velocity (V) times the wing area (A).


came from: https://wright.nasa.gov/airplane/drageq.html

To Overcome Aerodynamic drag, the formula is;
P^d = F^d · v = ½pv^3AC^d .
THE MAJOR SECRET
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Community Suggested Formulas
There is a physics law that always slows down rotating objects by -30%/s or -2%/tick. It can be expressed by this formula: b(0.7)^s or for ticks: b(0.7)^s/40
b = Initial angular value
s = Seconds

This phenomenon gives the illusion that free bearings have resistance when they indeed do not have any. -Mio,


39 Comments
Autismo 4 May, 2024 @ 8:52pm 
Sweet! now I get to skip physics class. Thx man!
Videxx 4 Dec, 2023 @ 6:53pm 
i understand skibidi toilet more than this
Piano Man  [author] 4 Dec, 2023 @ 4:19pm 
collisionless braincells would mean super compact ones :/
MaxNoDifference 1 Dec, 2023 @ 5:14pm 
Your brain must have its own gravitational force.
Piano Man  [author] 25 Nov, 2023 @ 6:58pm 
eventually maybe
Astronut 22 Nov, 2023 @ 5:52pm 
Make the new guide image a nerd emoji please
Piano Man  [author] 25 Oct, 2023 @ 9:42am 
yeah
JKkienzle 23 Oct, 2023 @ 5:05pm 
why does this make me think even though im reading answers to a equation that i've never seen ever in my life
Piano Man  [author] 10 Dec, 2022 @ 6:45am 
me too
awsd123 5 Dec, 2022 @ 6:35pm 
My head hurt