If an object with a mass of #2 kg # changes speed from #2m/s# to # 7m/s#, by how much does its kinetic energy change?

1 Answer
Feb 17, 2016

Answer:

#Delta E_k=45J#

Explanation:

#E_(k f) " :final kinetic energy"#
#E_(k i):" initial kinetic energy"#
#Delta E_k=E_(k f)-E_(k i)#
#Delta E_k=1/2*m*(v_f^2-v_i^2)#
#Delta E_k=1/2*2(7^2-2^2)#
#Delta E_k=49-4#
#Delta E_k=45J#