# Question #96f24

##### 2 Answers

Have a look:

Here's how you could approach this problem.

Think about the *conservation of energy*. The man starts atop of the bridge with only **potential energy**. At the bottom of his drop, when the cord is fully stretched, he will end up with only **elastic energy**.

All the *change* in potential energy will now be stored in the bungee cord. Assuming that the stretch in the bungee cord is equal to

Since you know the length of the bungee cord to be equal to **20 m**, you can write

At the bottom of the fall, you have

The elastic energy depends on the *stretch of the bungee*, which is

As a result, you'll have

Thus, the total distance of the fall will be equal to

The maximum force will be exerted when the cord is at maximum stretch

The maximum velocity during the fall will occur just before the bungee cord starts to stretch, i.e. after **20 m** of free fall. Use the equation

Solve the above equation to get the *time of free fall*

Now use the equation