Estimating Distance Travelled by Inclined Pendulum Homework

[captainjack2000]

Homework Statement

A train is traveling at 30m/s and decelerates and stops. During this process a passenger notices that a penduum is inclined by 10 degrees to the vertical. Estimate how far the train travels before coming to rest

Homework Equations

The Attempt at a Solution

I have drawn a diagram of the pendulum hanging from a string with tension T at an incline of 10 degrees to the vertical. The tension will have two components
Ty=Tcos(10)=mg and
Tx=Tsin(10)=ma
Tx will be the net horizontal force on the pendulum

rearranging I got tan(10)=a/g

then using v^2=u^2+2as
s=(v^2-u^2)/2a
=(0-30^2)/2gtan(10)=260.415m which seems a big too large

 

[gabbagabbahey]

I haven't checked your numbers, but your method looks fine. (And 260m doesn't seem like too large a stopping distance for a TRAIN to me)