A model train, with a mass of #4 kg#, is moving on a circular track with a radius of #3 m#. If the train's kinetic energy changes from #4 j# to #15 j#, by how much will the centripetal force applied by the tracks change by?

1 Answer
May 9, 2017

Answer:

#22/3N#

Explanation:

we know that the change in kinetic energy of the system
#DeltaE_k=1/2m(v_f^2-v_i^2)#

we also know that change in centripetal force is
centripetal force =#(mv^2)/r# or change in centripetal force =#m(v_f^2-v_i^2)/r#
so we gonna substitute the values we get

#(v_f^2-v_i^2)=2*DeltaE_k/m=11/2#

we put this value in centripetal force change equation we get

#m*11/2*1/r=(4*11)/(2*3)=22/3N#