Speed of a truck wthout brakes down a hill

AI Thread Summary
To determine the speed of a truck descending an 85-meter vertical hill with failed brakes, one can equate the potential energy at the top to the kinetic energy at the bottom. The truck's weight is 100,000 pounds (approximately 45,359 kg) and it starts at a speed of 50 km/h. The calculations involve using gravitational potential energy and kinetic energy formulas to find the final velocity. The discussion emphasizes the importance of showing the approach and equations used in the calculations. This method will provide the necessary speed at the bottom of the hill.
jamilm9
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1. Hi,
I'm trying to find the speed that a truck rolling down a hill which brakes have failed. The hill has a drop of 85 meters vertically and a horizontal of 1510 meters. The hill is like a right angle where the bottom right is the 90 degrees. The bottom left is 3.2 degrees and the top right is 86.8 degrees according to my calculations. Assuming the truck weighs 100 000 pounds or 45359 kg and has a starting speed of 50 km/h at the top of the hill what is the speed at the bottom of the hill. Can you please show all your equations so I can sub in any values that I need to.
Thank You
 
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Hi Jamilm9! welcome to PF!

you need to show your approach here, if you are stuck we will help you.

however, try to equate the potential energy at top with kinetic energy at the bottom and find velocity.
 

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