After the box comes to rest at position x1, a person starts pushing the box, giving it a speed v1. when the box reaches position x2 (where x2> x1), how much work wp has the person done on the box? assume that the box reaches x2 after the person has accelerated it from rest to speed v1. express the work in terms of m, v0, x1, x2, and v1.

As we know by work energy theorem

total work done = change in kinetic energy

so here we can say that wok done on the box will be equal to the change in kinetic energy of the system

initial the box is at rest at position x = x1

so initial kinetic energy will be ZERO

at final position x = x2 final kinetic energy is given as

now work done is given as

so we can say

so above is the work done on the box to slide it from x1 to x2

! 55 !  

write a paragraph or story to explain the transformation between potential and kinetic energy as shown in your picture or model.  

you should have at least 5 complete sentences with a main idea and supporting details.  

you must include the following words:  

potential energy

kinetic energy

mechanical energy

conservation of energy

dude, this is hard lol : ))