# How much work? Given speeds and mass

1. Apr 5, 2008

### ital_dj

1. The problem statement, all variables and given/known data
How much work is done by an Olympic triathlete who accelerates herself on her bicycle (combined mass of 105kg) from 5m/s to 10m/s

2. Relevant equations
W = mg$$\Delta$$d

3. The attempt at a solution
Tried solving for d, and plugging in.

2. Apr 5, 2008

### Snazzy

Your equation would apply if there was gravitational energy involved, but in this question there isn't. Work here is defined as W = Fd where F = ma.

3. Apr 5, 2008

### ital_dj

But still, how would I solve for d?

4. Apr 5, 2008

### Snazzy

Use kinematics to solve for a and d simultaneously.

5. Apr 5, 2008

### magda3227

W = delta(KE)

All you need to do is subtract her final kinetic energy from her initial kinetic energy to find the answer.