Jump to content

Recommended Posts

  • Iconoclast
  • Donating Members
  • Member For: 20y 6m 22d
  • Gender: Male
  • Location: CH

The SI units I will use are

Kg = Mass - SI - Kilogram -Derived from a peice of alloy kept in Paris (not hilton) which ALL accurate measurements of mass are based....,.

m = Length -SI- metre- Originally one ten millionth of the distancefrom the poles to the equator, found to be innacurate and is now measured in terms of the wave lenght of a krypton isotope.

s = time - SI second- Originally 1/86400 of the mean solar diary, is now accurately defined in terms of the period of vibration of the caesium atoms.

Mass, length and time are called fundimental quantities......

Quantities built from here are called derived quantities.........

You will be familiar with speed = distance/time

or speed = distance divided by time ( for you dumb people that dont know what / means)

Area is usually measured length by length

Therefore

Speed = m/s

Acceleration = (m/s)s or m/s ²

Force = Mass x acceleration = kg m/s²

Work = force x distance (kg m/s²)m or kg m²/s²

Power = work over time (kg m²/s²)s or kg m²/s³

Momentum = Mass x speed – kg m /s

Uniformly accelerated linear motion (drag racing)

s=1/2 (v+u)t

Time = 0.5 x terminal velocity plus initial velocity multiplied by time

A = (v-u)/t

Acceleration = velocity minus initial velocity divided by time

s = ut + ½ at²

Handy for acceleration

v² = u² +2as

Momentum (this is why your brakes don’t work)

F = ma

Force = mass x acceleration

OK… Quick question…. Easy one….

If you are travelling at 36km/h(10 m/s) and you want to accelerate to 100km/h (27.7 m/s) how much force do you need to apply if you want to do it in 3 seconds in an 1660kg XR6T…

OK

t=3

v=27.7 (=100km/h remember we have to work in m/s)

u=10

m=1660

Force = mass x acceleration

force

F=ma

Mass = 1660

Acceleration

A = (v-u)/t

V=27.7-10/t

V=17.7/t

T=3

17.7/3=a

=5.9 m/s²

Force = mass x acceleration

a

b

c

Work it out…….

my brain hurts now I am going to bed....

need help keep this thread alive and we can answer our own dumb questions

Link to comment
https://www.fordxr6turbo.com/forum/topic/16806-calculations/
Share on other sites

  • Member
  • Member For: 20y 5m 3d
  • Location: Mexico

To complete your calc you also need to know:

-Coefficient of friction on the wheels,

-Torque which will also include assuptions on wheel radius,

Slop on which your car is on otherwise you will need to make allowance for gravity

-Air resistance (drag)

probably many other factors but my head hurts LOL

Edited by Turbofalke
Link to comment
https://www.fordxr6turbo.com/forum/topic/16806-calculations/#findComment-240018
Share on other sites

  • Artificially Aspirated
  • Member
  • Member For: 21y 3m 7d
  • Gender: Male
  • Location: Brisbane
  Turbofalke said:
To complete your calc you also need to know:

-Coefficient of friction on the wheels,

-Torque which will also include assuptions on wheel radius,

Slop on which your car is on otherwise you will need to make allowance for gravity

-Air resistance (drag)

probably many other factors but my head hurts LOL

<{POST_SNAPBACK}>

:w00t2: I am glad I am not the only one... I started to write but could not be bothered. However I will add some more... Traction of tyres? would they instantly hook up? I know a few forum members can break traction at those speeds with ease. Also are you assuming in your calculation the XR6T in question would make its maximum power from idle to redline?

Link to comment
https://www.fordxr6turbo.com/forum/topic/16806-calculations/#findComment-240066
Share on other sites

  • Member
  • Member For: 21y 9m 30d
  • Location: Birkdale
  Blown BA said:
  rednut99 said:
I did all this in grade 10.

<{POST_SNAPBACK}>

And did you pass :laughing:

<{POST_SNAPBACK}>

Sure did, then when I went to uni I ended up having to do all the physics from hi-school again in 1 semester. So I've done it all twice!

Link to comment
https://www.fordxr6turbo.com/forum/topic/16806-calculations/#findComment-240141
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
  • Create New...
'