An object with mass 0.200 kg is acted on by an elastic restoring force with force constant 10.0 N/m. (a) Graph elastic potential energy U as a function of displacement x over a range of x from - 0.300 m to + 0.300 m. On your graph, let 1 cm = 0.05 J vertically and 1 cm = 0.05 m horizontally. The object is set into oscillation with an initial potential energy of 0.140 J and an initial kinetic energy of 0.060 J. Answer the following questions by refer-ring to the graph. (b) What is the amplitude of oscillation? (c) What is the potential energy when the displacement is one-half the amplitude? (d) At what displacement are the kinetic and potential energies equal? (e) What is the value of the phase angle ? if the initial velocity is positive and the initial displacement is negative?
Tuesday, March 7, 2017 Mountain Climate (Part 4) • Distribution of water on Earth Unique properties of water • • Adiabatic process • Water-related weather processes Distribution of Earth’s Water • 97.2% of water on Earth is saline • Of that 2.8%, most (87%) locked up in glaciers/icecaps or deep underground • Only 0.01% makes up all surface water resources! • Water moves through the Earth system via the hydrological cycle • Antarctica contains 70% of the Earth’s freshwater, 90% of the Earth’s ice Unique Properties of Water • Exists in all three states in moderate temperatures • Readily bonds, but is extremely stable • Dissolves many chemicals • Has extraordinary heat characteristics • Hydrogen bonding locks water molecules together, creating powerful tension