Physics

To solve this problem, we will use the work-energy theorem, which states that the net work done on an object is equal to its change in kinetic energy.

 

Given:

Mass of the fireman,

Height of the pole (distance fallen),

Frictional force,

Initial velocity, (since he slides from rest)

Gravitational acceleration,

 

Calculate the work done by gravity

The work done by gravity is equal to the gravitational force times the distance moved in the direction of the force.

 

Where the gravitational force .

 

 

Calculate the work done by friction

The work done by friction is the force of friction times the distance, but it acts in the opposite direction to the motion, so this work will be negative:

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