1. A speed racer loads his suspension up for a leap into the air over an oil slick his opponent dropped in front of him. His suspension is made up of four identical spring, each with k12000 N/m. A machine punches his suspension down, so the four springs are locked with a compression of 0.3m. How much PE is stored in this system? If he punches the jump button, how high will his car travel if it weighs 500kg?Please indicate which equation you use, what variable corresponds to each number, and how you got the number that goes with the variable.Thanks!
PE of one spring (1/2)kx^2 So, for the whole system, multiply by 4: PE 4*(1/2)kx^2 2(12000 N/m)(0.3 m)^2 2160 J Then, use conservation of energy: elastic PE lost gravitational PE gained mgh 4*(1/2)kx^2 h 4*(1/2)kx^2 / (mg) 2160 J / [(500 kg)(9.8 m/s^2] 4.40816327 * 10^-1 m Rounding to one sig fig (x 0.3 m), the PE stored in the system is 2 * 10^3 J. The car would jump 4 * 10^-1 m.
