6 - WorkPowerEnergy - Elastic Potential and Thermal

University:
High School
Course:
High School Physics
Academic year:

2024
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372

Pages:

10
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Unit 5: Work, Power and Energy Conservation of Energy with Elastic Potential (Ee) and Thermal (Q) Energy 5.9 Adding Ee to Conservation:  Ex#1 A 50.0g metal ball compresses a spring (lying flat on a frictionless floor) with a force constant of 10.0N/m by 8.00cm. What is the speed of the ball when the spring is uncompressed? Compressed Ee Ek k = 10.0N/m m = 0.0500kg x = 0.0800m v = 0 m/s Uncompressed Ee k = 10.0N/m x=0m Ek m = 0.0500kg v=? ET = ET Compressed Uncompressed Ex#2 A 100.0g ball sits on a compressed spring (200.0N/m). It is compressed 10.0cm as it sits on a table and the ball is 1.50m above the floor. The ball is launched upward. What is the height above ground of the ball when it has a speed of 4.00m/s? Compressed Eg Ee m = 0.100kg k = 200.0N/m Ek m = 0.100kg h = 1.5m v = 4.00m/s x = 0.100m End Eg m = 0.100kg h=? ET = ET Compressed End  5.10 ◼ Thermal Energy (Q): The energy stored in an object with temperature and specific heat capacity. specific heat capacity in J/kgᵒC unit of Q is J (it is energy) temp in ᵒC mass in kg Ex#3 If 1000.0J of thermal energy is added to 200.0g of water (c=4184J/kgᵒC), by how much does the temperature increase? Ex#4 The specific heat capacity of iron is 462 J/kgᵒC and its coefficient of kinetic friction is 0.150. If a 100.0g block of iron slides to a stop along a flat floor from 5.00m/s, by how much does its temperature increase during the slide? Solve Ff and d: work done by friction goes into thermal energy F_app = 0 Ex#4 Solve Ff and d: work done by friction goes into thermal energy