A model train with a mass of #4 kg# is moving along a track at #18 (cm)/s#. If the curvature of the track changes from a radius of #84 cm# to #42 cm#, by how much must the centripetal force applied by the tracks change?

1 Answer
Mar 22, 2018

Answer:

The change in centripetal force is #=0.155N#

Explanation:

The centripetal force is

#vecF_C=(mv^2)/r*vecr#

The mass is of the train #m=4kg#

The velocity of the train is #v=0.18ms^-1#

The radii of the tracks are

#r_1=0.84m#

and

#r_2=0.42m#

The variation in the centripetal force is

#DeltaF=F_2-F_1#

The centripetal forces are

#||F_1||=4*0.18^2/0.84=0.154N#

#||F_2||=4*0.18^2/0.42=0.309N#

#DeltaF=F_1-F_2=0.154-0.309=-0.155N#