[Bošnjo 44]

sonata-LPG kaže:

Ova formula ti je obična kurčevina, barem u poznatom svemiru. Čak ni američka formula ne izgleda tako. Vidim, gradivo si fino savladao.

https://www.forum.hr/showpost.php?p=4...1&postcount=17

Through force, work, distance and time to power
In order to move a weight over a distance you need a force. If the weight is glued to the ground and therefore doesn't move, no work will be done (at least not in a physical sense). So work is the movement of a weight across a distance (by applying a force). If you take the time into account now, you can calculate the power. Power is the duration of work, the time it takes to move a weight a certain distance. The more weight you move in a period of time the more power (ability to do work over time) you 'have'.

Let's play engine and stick a weight of 1N (= 0.102 kg) to the end of a stick that is 1m long and that you are trying to hold horizontally by grasping it at it's opposite end. The (twisting) force that is necessary is 1N × 1m = 1Nm.
Now imagine rotating that stick with the weight at the other end around 360° against a resistance of 1N. The work done will be 1N × 6.2832m = 6.2832Nm (6.2832m is the perimeter of the circle the weight at the end of the 1m-long stick moves along. Perimenter = Diameter × Pi = 2 × 1m × 3.14159... = 6.2832m).
The resistance of 1N is there to simulate the gravitational force you would have to deal with when moving the weight vertically. So if you'd lift a weight of 1N 6.2832m vertically you had done the same work of 6.2832Nm.

But what about the power to do so? Now time has to be involved, as you can see by looking at the definition of a horsepower: 1hp = 75kp × m/s. 1kp (kilopond) is equivalent to 9.80665N, so 1hp = 735.5N × m/s which means that when lifting a weight of 735.5N (75 kg) one meter every second that's the power of one horsepower. Lifting twice the weight in the same time will double the power (2 hp) as will lifting the same weight in half the time and so on. More work (in the eyes of a physicist!) would not be done though, because the formula 'force × distance' does not care about time.

In order to return to cars and engines, let's take the BMW 850CSi for example. The engine of this car will produce 380 hp at 5300 rpm. So you could lift a weight of 380 × 75 kg = 28500 kg one meter every second!

The unit of horsepower is N × m/s. In our example with the weight and the stick the unit of the work was N × m (Nm). If we multiply this by the rpm (unit 1/s) we get the unit of power. If you're looking somewhat sceptical now, that's a common reaction. So let's calculate at which rpm 1 Nm of work equals 1 hp:

1 hp = 75 kp × m/s = 735.5 N × m/s

Now we set this equal to our torque multipiled by the still unknown rpm and get

735.5 N × m/s = 6.2832 Nm × n 1/s
Now we can compute n:

n = 117.058

An engine which has 1 Nm of torque at 117.058 revolutions per second (that is 7023.5 revolutions per minute) then has the power of 1 hp. With that information it is easy to get the following formula to calculate the power:

hp = Nm of torque × rpm/7023.5

Gle, momak, prvo postavljaš priglupa pitanja zašto je fabia dizel sporija za mizeran postotak od fabie benzinca, a imaju istu snagu. Elem, onda ignoriraš razliku u masi. Pa jasno da je auto koji je 5% veće mase ujedno 5% slabijeg ubrzanja. Kad ti se objasni da je to zbog mase, onda kažeš da je to kurčina i da te teorije padaju u vodu i postaš neki primjer tablica kojeg, kao što ti je i Wonder objasnio - nitko ne gleda.

toliko si sjeban da si se pogubio
riječ je o istim dizelašima, jedan 75 ks drugi 80 KS, oba 1.4 tdi, dakle ISTA MASA, jadan bio

sonata-LPG kaže:

Uostalom, kad navršiš 18 i sjedneš u pravi auto, možda će ti neke stvari biti jasnije.

ja 18 godina VOZIM, jadan bio