Activity B (continued from previous page) Calculate: Gravitational potential energy (U) depends on three things: the object's mass (m), its height (h), and gravitational acceleration (g), which is 9.81 mis2 on Earth's surface: Uzmgh Energy is measured in joules (J). One joule is equal to one 1 kg-mzisz. When calculating the energy of an object, it is helpful to convert the mass and height to kilograms and meters. (Recall there are 1,000 grams in a kilogram and 100 centimeters in a meter.) What is the mass of the 50-gram car, in kilograms? Set Hill 1 to 75 cm and the other hills to 0 cm. What is the height in meters? What is the potential energy of the car. in joules? Calculate: Kinetic energy (K) depends on the mass and velocity of the object. (Velocity is the speed and direction of an object.) The equation for kinetic energy is: With Hill 1 set to 75 cm, click Play and allow the car to reach the bottom. What is the final velocity (speed) of the car, in meters per second?_ What is the kinetic energy of the car, in joules? (Use the mass in kg.) How does the car's kinetic energy at the bottom of the hill compare to its potential energy at the top