A moving cart with a mass of 7.1 kg hits a spring, traveling at 20.7 m/s at the time of contact. At the instant the cart is motionless, how much energy is converted into elastic
energy?

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )