Which Path Requires the Most Energy Suppose that

Which Path Requires the Most Energy? Suppose that a car traveled up three different roadways (each with varying incline angle or slope) from the base of a mountain to the summit of the mountain. Which path would require the most gasoline (or energy)?

Work-Energy Principle In order to transfer energy to an object, you have to exert a ______ on that object Force

Work-Energy Principle work done The amount of energy transferred by a force is called the w_____ WORK DONE= ENERGY TRANSFERRED d_____ by that force.

Work-Energy Principle Whenever w_____ is done on an object, it’s energy changes. . . the energy is t____ to that object Work (F • d) transferred

Work-Energy Principle

Work-Energy Principle This actually a Formulas: special case of the Worknet =ΔKE Conservation of =KEf- KEi Energy ½mv² = f- ½mv²i F • d =ΔKE

Work-Energy Principle

Work-Energy Principle #10 Homework Worknet= ΔKE F • d ½mv²f= ½mv²i A 13 g bullet is accelerated in a rifle barrel 46. 8 cm long to a speed of 522 m/s, use the work-energy theorem to find the avg Force exerted on the bullet while being accelerated

Work-Energy Principle #9 Homework Worknet= ΔKE mgh =½mv²f- ½mv²i A 0. 8 kg rock slides horizontally off a table from a height of 1. 2 m. The speed of the rock as it leaves the thrower’s hand at the edge of the table is 2 m/s. 1) Solve for time What is the KE of the rock just before it hits the floor?