Search the forum,

speed

In everyday use and in kinematics, the speed (commonly referred to as v) of an object is the magnitude of the rate of change of its position with time or the magnitude of the change of its position per unit of time; it is thus a scalar quantity. The average speed of an object in an interval of time is the distance travelled by the object divided by the duration of the interval; the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero.
Speed has the dimensions of distance divided by time. The SI unit of speed is the metre per second (m/s), but the most common unit of speed in everyday usage is the kilometre per hour (km/h) or, in the US and the UK, miles per hour (mph). For air and marine travel the knot is commonly used.
The fastest possible speed at which energy or information can travel, according to special relativity, is the speed of light in a vacuum c = 299792458 metres per second (approximately 1079000000 km/h or 671000000 mph). Matter cannot quite reach the speed of light, as this would require an infinite amount of energy. In relativity physics, the concept of rapidity replaces the classical idea of speed.

View More On Wikipedia.org
Recent contents Top users
  1. J

    Myson Kick space heater

    I cannot get my Myson kickspace heater to operate on low fan speed. I have checked the wiring and it looks okay. The fast fan speed works okay both in hot and cold mode so I presume the thermostat attached to the water pipe must also be working okay. Does anyone know what the likely cause of...
  2. S

    grundfos alpha 2l 15 50 ----- not pumping

    hi all, about 3 weeks ago i fitted said pump and all was fine. but 2 days ago we started getting noises, banging etc. when i looked at the pump the power light was on, but not the speed setting light and the pump wasn't working. i unplugged the jack plug, then reconnected, the power light and...
  3. K

    Help and advice for the correct replacement pump for my microbore system

    I need some advice as to the correct circulating pump to fit to an existing microbore system on my domestic two story semi-detached house. The system was installed many years ago and works on a baxi Bermuda back boiler, the system is clean and the boiler is well maintained and working fine...
    • knurly
    • Thread
    • advice boiler correct help microbore pressure pump replacement speed system water
    • Replies: 19
    • Forum: Plumbing Jobs | The Job-board
  4. M

    JG Speed Fit vs Nu Heat UnderFloor heating

    Dear people, I am in a dilemma as to which UFH to use to heat the floor in my diner/lounge and utility room. I presume I have 2 zones - one utility room (5 sqm) and the other is the lounge (45 sqm). These are the only rooms i am having UFH. JG Speed fit materials etc will cost me rouhgly 1200 vs...
    • manorpurl
    • Thread
    • heat heating speed ufh under floor heating underfloor underfloor heating
    • Replies: 4
    • Forum: Plumbing Jobs | The Job-board
  5. T

    What's your internet speed?

    Posting up for Keefy as he is having troubles posting due to his internet. Run this and post up your results. Speedtest.net by Ookla - The Global Broadband Speed Test Here is mine - Cheers
  6. L

    forum speed!!!!!!!!

    Is it just my lap top or has the site been changed over the last few weeks, as I keep having to reload it when making comments on threads etc, its becoming a right pain!!!!!!!
  7. S

    speed fit on secondary return

    Just changing some dodgy waste pipes on a dubious bathroom job installed by a DIYer putting speed fit in as some has already been fitted in for some time before ,then notice's the unvented has a secondary return fitted.Do I finish it off in plastic and get done for lunch,or do I rip it all out...
  8. I

    two pumps

    Hi I installed a 250l unvented cylinder on a top floor of a 4 storey house, the pump and boiler are in the basement, the pump (Grundfos 15-50 5m head) the heat is just getting to the cylinder on the flow but the pump isnt quite man enough to pump it through the coil and back on the return...
  9. D

    Y plan intermittent problem-no heating!

    Afternoon all, As title suggests, customer has an intermittent fault with their heating, sometimes it does not come on but both times I have been out to look, it is working! My initial thought was 3 port valve but looks as if it has been replaced (paint stripped either side of nuts!) I am...
  10. B

    Rayburn 460k - boiler motor changes speed....

    Anyone had this? Its the older 460. Its weird, the motor starts fairly slowly then speeds up and flutuates slightly. Im tempted of course to cry "new motor' but anyone seen this before?
  11. N

    diamond core drill????

    Need a core drill but tired of spending money on tools:bigcry::bigcry:. These look cheaper than the dewalts/makita's etc: PDP PD162 Dry Diamond Core Drill 240V (PD-162) Any one used or heard about them? worth a shot ? Or is it another one of those you get what you pay for so just bite the...
  12. J

    tap hole cutter

    A customer has ordered a tap but the pipework won't fit through her tap hole on the stainless steel sink , a mate said there is a cutter device on the market to make the tap hole bigger can anyone point me into the right direction as to what they are and where they are . Please don't say hole saw
  13. turnpin

    Speed up Croppie

    Come on Croppie only 5 more posts for your 4000 post badge ...always quality info regards turnpin:shades_smile::shades_smile:
  14. D

    speed dreams

    beeb2, proper engineers :)
  15. B

    new speed camera

    just seen this on FB sneaky or what
  16. R

    ferroli optima 700

    just been up to my daughters new flat in leeds:driving: and gave the gas plumbing and heating a good check over (as you do)lol. the landlord arrived as i just finished so gave him an earache of the problems and faults that i had discovered:boxing_smiley: such as; gas pipe to cooker hanging of...
  17. A

    Has GasSafe changed in the past 2 years?

    Hi im looking to re-register shortly and was wondering what has changed in the past 2 years has information on there website improved etc etc? also are there any new things with which i will need to be brought up to speed on? Cheers
  18. L

    pump speed

    Hi just posted but forgot to ask another question.... how do figure out the correct pump speed on an open vent sysytem and what are the problems if you do not. cheers
  19. M

    Broadband speed

    My internet seems to running really slow so i did a speed check using the one on the bbc website which showed 4.5mbps as my broadband is with talk talk I thought i'd check with their speed checker and guess what, I'm getting 11.5mbps and my internet is apparently running as fast as it can...
  20. D

    British gas 330+

    Working on a house with the above boiler and noticed when I turned it on it ignited with a bit of a bang. The customer says it often does this and has on occasion gone to F1( tried to ignite 5 times without success). Does any body have any ideas or are familiar with this boiler , I would have...
Creating content since 2001. Untold Media.

Newest Plumbing Threads

BS 5389 Tiling Standards
Contractor Advice Forum
DIY Advice
Electrical Blog
Tiling Advice
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock