A 12.5-tonne tractor develops a maximum first-gear rimpull of 6300 kg on a 2% upgrade with a 45 kg/tonne rolling resistance. Determine the towing pull available for a load________________?
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Answer: B. 5515 kg
Explanation
Subtracting grade and rolling resistance losses from total rimpull leaves net towing pull. Resistance forces acting against the tractor reduce the available drawbar pulling capacity. Calculating grade and rolling resistance values allows accurate net pulling force determination. Rimpull is the tractive force developed between rubber tires and the driving surface. Grade resistance opposes vehicle movement on upgrades proportional to total vehicle weight. Rolling resistance accounts for tire flexing and surface deformation losses during travel.
Earthmoving contractors calculate net towing pull to ensure tractors can haul loaded scrapers. Accurate performance sizing prevents equipment stalls and maintains high site productivity. Job site slopes and soil conditions dictate the effective hauling capacity of heavy machinery. Option A underestimates available towing pull due to an incorrect resistance subtraction. Option C overestimates towing pull by ignoring specific grade resistance components. Option D results from improper calculation of tire rimpull and surface resistance losses.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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