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JamesB93

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I'm working through my Mechanical Principles: Dynamics assignment now and I've hit a wall on a question and just can't figure out how to advance.

The question word for word is:

Part 1:

A Manual 5-speed Vauxhall Corsa 1.4 16v with an all-up mass of 1,260kg is used to drive up a hill with an incline of 10% at 65km/hour.

If the driver applies the brakes as if undertaking an emergency stop and slows the car down to 30km/hour in 2.5 seconds, calculate the distance traveled under braking and the energy dissipated in each of the 4 brakes if the front:rear braking effort is split 60:40. Ignore all friction and aerodynamic losses.

If the driver now coasts up the hill until the car comes to a rest, calculate, ignoring losses due to friction and aerodynamics, the additional distance traveled and the potential energy increase whilst coasting.

Part 2:

The engine has a bore of 77.6mm and a stroke of 73.4mm. If the volumetric efficiency is 44% and the pressure drop at the inlet is 55% of atmospheric pressure at an engine speed of 6,000rpm, calculate the power output at the flywheel when the calorific value of the fuel is 47,850kJ/kg.K. Take atmospheric pressure as 1.01 bar, ambient temperature as 20C and the mass air/fuel ratio as 14.7:1/

If the car is driven at an engine speed of 6,000rpm in 3rd gear with a gear ratio of 1.41:1 with a final drive gear ratio of 3.94:1. calculate the driveline torques at the output of the gearbox if the efficiency of the gearbox is 97% and the final drive efficiency is 89%.

Now I think I'm fine on part 1, I seemed to do all the calculations there with relative ease, but on part 2 I've completely hit a brick wall, if someone could take me through the correct method of calculating the answers without giving me the answers I'd greatly appreciate it. My first attempt at calculating this indicated that this 1.4 litre Vauxhall was outputting 6,350bhp and using 168 litres of fuel a second so I know I'm going insanely wrong somewhere.

This is my first forum post so if I've misplaced my post or broken any rules please let me know (but don't tell me off :().