If an object with a mass of # 3kg # changes speed from #5m/s# to # 3m/s#, by how much does its kinetic energy change? Physics Work and Energy Energy 1 Answer ali ergin Feb 9, 2016 #Delta E_k=-24 J# Explanation: #Delta E_k=1/2*m(v_l^2-v_i^2)# #Delta E_k=1/2*3(3^2-5^2)# #Delta E_k=1/2 *3(9-25)# #Delta E_k=1/2*3(-16)# #Delta E_k=-24 J# Answer link Related questions How do matter and energy interact? Question #50ca2 Question #242cf Question #5038d Question #50391 What is potential energy? Question #d6576 Question #50cae Question #50cb2 Question #50cb6 See all questions in Energy Impact of this question 1340 views around the world You can reuse this answer Creative Commons License