# Potential/kinetic energy

1. Dec 14, 2005

### cheez

Is it a energy conservation problem? Can I ignore the spring part? And how to calculate the energy that used by work done?
thanks!

2. Dec 14, 2005

### cheez

ps:work done on friction.

3. Dec 14, 2005

### andrewchang

$$W = F d cos( \Theta )$$

and yes, it is a conservation of energy problem. The spring is important, though.

4. Dec 14, 2005

### andrewchang

do you mean work done _by_ friction?

5. Dec 14, 2005

### Staff: Mentor

Yes, I would approach it with energy conservation since that is usually easiest. Is there any potential energy stored in the spring? If so, then you cannot ignore the spring. Don't forget the energy that goes to heat from the friction on the snow.

-Dale

6. Dec 14, 2005

### kp

yes..what is the term for the potential energy of a spring?

what is the term for kenetic energy?

7. Dec 14, 2005

### andrewchang

$$EPE = \frac {1}{2} kx^2$$
$$KE = \frac {1}{2} mv^2$$

do you have any textbooks? or notes? these equations are important ones that you should already know.
\
EDIT:

just kidding. i thought kp was actually asking for the equations. sorry!

8. Dec 14, 2005

### -Christastic-

Just have to say that I love that diagram.

9. Dec 14, 2005

### cheez

I wanna know what's wrong with my steps, cuz I don't get the answer. The answer is 33.8m

10. Dec 14, 2005

### kp

check your numbers again because your set-up is right, I got 33.77meters