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.

Explanation:

First, the box goes from position x=0 to x=x1, so, the work made by the friction is calculated as:

where is the force of friction, the displacement, m the mass, V is the speed in rest and the initial speed.

V is equal to zero, so:

it means that the force of friction is equal to:

On the other hand, when the box goes from position x=x1 to x=x2, the work-energy theorem said that:

Where is the work done by the person.

Then, solving for :

Finally, replacing by , we get:

freezing

deposition

condensation

explanation;

melting also called fusion is the process where solid becomes liquid, sublimation is the process where solid becomes gaseous without first changing to liquid, deposition involves change from gaseous to solid state, freezing involves change from liquid to solid, boiling or evaporation involves change of liquid to gaseous state, while condensation is the change from gaseous state to liquid state.

endothermic reactions involves absorption of heat from the surroundings or the environment while exothermic reactions involves loss of heat energy to the surroundings.

in this case, sublimation, evaporation and melting are endothermic reactions (gain energy from the environment) while, freezing, deposition and condensation are exothermic (loss of energy to the surroundings) reactions.

i don't know that i agree with that but what's the question ?