A model train with a mass of #3 kg# is moving along a track at #3 (cm)/s#. If the curvature of the track changes from a radius of #21 cm# to #18 cm#, by how much must the centripetal force applied by the tracks change?

1 Answer
Aug 13, 2017

The centripetal force changes by #=0.002N#

Explanation:

The centripetal force is

#F=(mv^2)/r#

The mass, #m=(3)kg#

The speed, #v=(0.03)ms^-1#

The radius, #=(r) m#

The variation in centripetal force is

#DeltaF=F_2-F_1#

#F_1=mv^2/r_1=3*0.03^2/0.21=0.013N#

#F_2=mv^2/r_2=3*0.03^2/0.18=0.015N#

#DeltaF=0.015-0.013=0.002N#