Q. When an 81.0 kg adult uses a spiral staircase to climb to the second floor of his house, his gravitational potential energy increases by 2.10 103 J. By how much does the potential energy of a(n) 20.0 kg child increase when the child climbs a normal staircase to the second floor?
Q. A 0.55 kg iron horseshoe that is initially at 515°C is dropped into a bucket containing 10 kg of water at 22°C. What is the final equilibrium temperature? Neglect any heat transfer to or from the surroundings.