The Physics Behind Parking :: physics science cars vehicles

BackgroundAfter a long day of cruising through town with your buddy, the two of you have large quite an appetite. You spot a McDonalds at the top of a very(prenominal) steep hill. Unfornately a local biker gang must of had the same idea. Encredibly, the lonesome(prenominal) available parking spot is on the street, uphill of nearly 15 Harleys. There be no other restaurants for 100 miles in both directions. Famished, your friend skillfully manuvers his machine to the side of the road. The breaks shudder as the car comes to a stop on the hill. He holds the brake, puts it into first, and shuts off the car.ProblemBikers dont cope kindly to people messing with their bikes. Your friend is about to let off of the brake. world the physics major you are, you have to decide whether its safe to park or safer to go hungry. Your friends car is pretty old, and the e-brake hasnt worked for years. The car will be held in place solely by the moter. There are two misbegotten looking bikers smo king outside entrance. They are watching you so there probably wouldnt be time to puddle a take out for it.Known What You KnowYour buddys car is classic, and Im sure he would want to make more than an educated guess. Ive done a little investigating to befriend you out a bit. I took a torque wrench to the beat back, and resists it resists aproximately 46 ft*lbs of torque at the crankshaft. After the compression bleeds down this flake is reduced to 38 ft*lbs. The cars rear differential has a 3.73 to 1 gear ratio and a manual transmission with a 3.35 to 1 ratio in first gear. The tires are 28 inches in diam and the gross weight of the car is approximately 2100 lbs. The hill is often travelled by truckers, and on the way up you noticed a family that said the hill was at a 26 degree move with the horizontal. SummaryWhen the car is at rest this means it is in a system of static equilibrium. Gravity is pushing forward on the car, and the tires are pushing back on the car via the r eaction force of attrition in the motor. The steeper the hill, the greater the force of gravity acting on the car, the greater the reaction force in the motor must have. As stated before, the maximum torque that can be applied to the motor before it rotates is 38 ft*lbs.