To solve this problem we will apply the concepts related to the conservation of energy. It is necessary to bear in mind that friction always acts opposite to the movement of the object and will therefore be negative to our reference system. This also leads us to intuit that the work done by this force is also negative.
[tex]W = \Delta E[/tex]
[tex]W = E_f -E_0[/tex]
The final energy is equivalent to the kinetic energy of the body while the potential energy will be the initial energy (stored at a certain height), therefore
[tex]W = KE-PE[/tex]
[tex]W = \frac{1}{2}mv^2 - mgh[/tex]
Where,
m = mass
v = Velocity
g = Gravity
h = Height
Replacing we have that
[tex]W = \frac{1}{2} (28)(3.2)^2 - (28)(9.8)(4.8)[/tex]
[tex]W = -1.174kJ[/tex]
Therefore the Work was -1.174kJ
The work done by the friction is 1173.76 Joules.
The movement of an object caused due to an external force applied on it in the direction of the displacement is measured by the work.
Given that Megans has a mass m 28 kgs. She climbed the ladder of height h 4.8 m with a velocity v of 3.2 m/s. The work done by friction is the total energy change during the work.
Work = Kinetic Energy - Potential Energy
[tex]w = \dfrac {1}{2}mv^2 -mgh[/tex]
Where, w is the work done by friction and g is the gravitational acceleration.
Substituting the values in the above equation.
[tex]w = \dfrac {1}{2}\times 28\times (3.2)^2 - 28\times 9.8\times 4.8\\[/tex]
[tex]w = -1173.76\;\rm J[/tex]
Hence we can conclude that the work done by friction is 1173.76 Joules.
To know more about the work, follow the link given below.
https://brainly.com/question/873722.
