Amarble of mass m rolls with initial speed v down a long, horizontal hallway. eventually, the marble comes to a stop. how much work has friction performed on the marble?

-mv2

mv2

0.5mv2

-0.5mv2

Explanation:

Given:

Mass of marble =

Initial velocity of marble =

Final velocity of marble = 0 as it comes to rest.

By work energy theorem:

Work done by forces acting on marble is given by :

Work done = Final Kinetic energy - Initial Kinetic energy

Kinetic energy can be calculate using formula:

where represents mass of body and represents velocity of body.

Final kinetic energy:

Initial kinetic energy

Work done by friction on the marble

the part of the wave he is travelling on is the crest