RichardTM

+80 for the loco ? 5880+80 =5960kN

1200 x 5 = 6000 But if I were to use gravity at 9,8 and not 10 id get 1 176 000N So 1176 x 5 = 5880kN F2=Fa+Ffr F2=0+5880kN F2= 5880kN

@klaynos I cant attach the image the image button is broken (the ok and cancel buttons don't work) and it wont allow me to paste links on to here @studiot 5N per kN of the mass: 120 000kg to N or kN 120 000x 9.8 = 1176000kN 5N to kN 5/1000 =0.005kN So 1176000/0.005 =235200000kN So F2=Fa+Ffr F2=0+235200 000 F2= 235200 000kN ? I don't think this is right (I was going to do a simultaneous equation with the 2 equations but I don't have Fa for the 1st equation.)

a= 0 because the question says constant speed. Or are we assuming a= 9.8 (gravity)? So would you be saying F= 120000x0 = 0 Is my answer ? Or just part ?

You don't see a strategy for solving this question because I don't know how to. Iv always been taught speed= distance/time no one has ever told or taught me a different way to work it out, that is why im so confused, Iv tried googling it, but it keeps telling me speed=distance/time. To my knowledge the question is asking for the force that need to be applied for the train to run or drive at a constant speed. Yes F=m.a Im understanding that I need to work out constant speed 1st to get/help work out my applied force some how, once iv got that applied force I can take away the friction or resistance force?

@studio If you wouldn't mind please seeing my 2nd post that should explain everything for me. Thank you Richard

Thank you I never knew Mg was a ton, no one ever told me that. I don't have time or acceleration(other than gravity) or distance Here is the exact question. 1.3 A train with a mass of 120 Mg accelerates uniformly on a horizontal track. The resistance to movement is 5 N per kN of the mass of the train. The force in the draw-bar of the locomotive is 80 kN. Calculate the following: 1.3.1 The force required for the constant speed. Constant speed = distance / time .But I don't have distance or time.

Hi I have a question about how to calculate constant speed, but im only given mass and a few forces and I know speed is distance over time. So now im not quite sure how I would calculate this. Given: A train is accelerating on a horizontal track. mass -> 120 Mg (I assume Mg is an error and making it tons) forces -> Resistance to movement is 5N per kN of the mass -> In draw-bar of the locomotive is 80kN (If needed I can type out the full question iv been qiven) Thank you Richard