Quick Science Question: Calculating Thermal Energy?

Question

A model rollercoaster car weighs 3 kg. If it reaches 5 meters, how much energy is transformed into thermal energy at that point? 

I have other values too (it's a multiple part problem):

• Gravitational Potential Energy at 'A' is 294.3 Joules and 'A' has a height of 10 meters
• Kinetic Energy at 'C' is 54 Joules
• Total Mechanical Energy of the coaster is 294.3 Joules

There's also a diagram that looks kind of like this:
         /^---A^----\                                                   

       /            \              /^--C^--\

      /              \            (        )    

     /                 \           (      )

__/                    \___B__\_  /_____D______

Basically, 'A' is the highest point, 'B' is after 'A' and has the greatest velocity, 'C' is the top of a loop-d-loop after 'B', and 'D' is a flat surface after the loop ('C').

 

Here's what I'm thinking:

 

First off, for point 'C', I have Kinetic Energy at 54 Joules. If I calculate Gravitational Potential Energy at point 'C', then I'd have 147.15 Joules because the height of 'C' is 5 meters.

Then, the Total Mechanical Energy for the entire roller coaster is 294.3 Joules.

However, 147.15+54=201.15.

So... does that mean that the remaining energy is thermal energy? Would that mean that the answer is 93.15 Joules?

Answer 1

description isn't complete.

147.15 Joules - this shows up once only. where it comes from? what is it??

you need the heights of A C points ...

 

Complete the problem, please. look what you are missing, and add ...

I'll be watching

 

 

================

 

Yessss !!!

 

You're absolutely correct - we must assume the missing energy went to thermal "activity".

 

I like it - job is very nicely done :)

 

Good luck!