Recent content by stephenn

Thanks for links, 'Mordred'... Your links are helpfull... the first article one especially... rotational velocity in relation to radius distance etc I've found another topic on these boards which is most interesting and have placed the link... should anyone else just reading this thread...

OK thanks, 'phinds'... so... the rotational speed of stars in the outer reaches = faster than the quantity of mass, seen to be around... (providing gravitational force) to balance the sums... to hold them in their place, as observed. * ... anyone know established papers with these...

Hello Dark matter is presumed... to balance the sums... as visible matter doesn't work out (apparently) to a high enough value... ... What part of the calculations was evaluated as being too high... to warrant the need for more matter to be 'somewhere'. Thanks for thoughts

for a fully loaded small car of 1100 kg with a speed: 30mph 48kmh (13.33m/s) and a uk highway code breaking distance of 14m I have found and use these two equations to give: 1. acceleration (decelleration) 2. brake force ... assuming brake force to be near to a maximum... the 2nd...

Thanks... gotit in end... didn't bother with the end equation... simply used first 2 equations in own right: * started with v2=u2+2as * then plugged that into F=ma * this got me to the answer All done Thanks for input, much appreciated

hello have found this interesting question (interesting to me)... along with an equation that is supposed to allow the answer... but I plug in the data and never get the same result as is correct. could someone set it out with the data so it flows to give -690N (if correct)... thanks (not...

very interesting... I understand the principle of aerodynamic downforces (on F1 especially) would increase contact forces of car on the planet surfaces... and so as you mention would displace water whereas a lighter massed or downforced car may aquaplane. Thanks for thoughts. Anyway, back...

very interesting... I've heard a story sample regarding friction: if a full size ship and a small replica (same materials) were placed on a slipway... then the slip way tilted sideways... which one would start to slide first? The answer was said to be... at the same time... because it was a...

Hello have a question and am interested to find a simple equation to include mass as a variable regarding stopping distances of a car In the UK highway code... a braking distance = 14m for a car at 30 mph (48 kph) my questions are... if you load the car up fully (increase mass)... then...

haha, I was prodding and poking at my sentence to get it more concise... got the equal and opposite bit... your "change" and neat phrasing gets a thumbs up, thankyou. :smile:

Thanks for reply... and workings... I understand that the phrase of half and half doesn't carry with it, the direction factor (one being opposite to the other). I still wish to test "worded" / "spoken" notions, that will hold true: so for the same notion: In the closed system...

Please verify this notion regarding... momentum Hello. Could someone verify this notion about momentum... thanks here is info: - The conserved closed system here, is a vehicle and the planet (via the road attached) - A stationary vehicle has no momentum - A moving vehicle has some...

momentum p is indeed mass m x velocity v p = mv mass... is not actually the weight... weight is mass x gravity... so mass of something is its weight then deduct any gravity it was weighed in ie earth, moon etc velocity... though is not actually speed... it is a speed and a...

Question about momentum... If I am to consider these three points as true: 1. A stationary car has NO momentum 2. A moving car HAS momentum 3. As momentum is a conserved property... So I am wondering where the momentum is conserved when A. The car goes from say 0 to 60 mph ... from none...