# Homework Help: A heat engine and determining Power

1. Mar 1, 2005

### JasonL

A heat engine operating between temperatures 500K and 300K is used to lift a 10KG mass vertically at a constant speed of 4 meters per second.

Determine the power the engine must supply to life the mass.

I'm having trouble finding an equation that could relate temperature and my other given variables..I think I need to get the Work done, thus I can calculate the power...anyone care to enlighten me as to how to go about it?

2. Mar 1, 2005

### Staff: Mentor

Hint: How much work is required to lift a 10 kg mass 4 m? Since the engine must produce that much work every second, how much power must it supply?

(I assume there is more to this question. Other parts will make use of the operating temperatures.)

3. Mar 1, 2005

### JasonL

You assume correctly(But I can do the rest myself), often times when reading a physics question over and over you still miss little things such as "per second", that are the keys to helping you solve a problem....Thanks Doc

I even typed it...sheesh...

4. Mar 2, 2005

### gschjetne

$$w = m g \Delta h$$
You'll get this in joules, times that one second gives you watts.