A model train with a mass of #4 kg# is moving along a track at #21 (cm)/s#. If the curvature of the track changes from a radius of #84 cm# to #140 cm#, by how much must the centripetal force applied by the tracks change?

1 Answer
Aug 29, 2017

Answer:

#8400 dy n e or 0.084N#

Explanation:

#m=4000g#

#v=21cm*s^(-1)#

#R_1=84cm#

#F_(c(1)) =( mv^2)/R_1#

# =(4000*21^2)/84#

# =21000" dyne"#

#R_2=140cm#

#F_(c(2)) =( mv^2)/R_2#

# =(4000*21^2)/140#

# =12600" dyne"#

Change in #F_c = F_(c(1)) - F_(c(2))#

#=21000-12600 " dyne" =8400" dyne" =0.084 N#