An object initially at an elevation of 5 m relative to earth’s surface with a velocity of 50 m/s is acted on by an applied force r and moves along a path. its final elevation is 20 m and its velocity is 100 m/s. the acceleration of gravity is 9.81 m/s2 . determine the work done on the object by the applied force, in kj

Explanation:

The work made by the force its equal to the change of mechanical energy

The mechanical energy is given by:

where is the kinetic energy and the potential energy.

We know that, the kinetic energy is

and the potential energy

We can put h=0 at Earth's surface, taking this in consideration, the initial Energy is:

the final Energy is:

The work will be:

As we don't know the mass, we can take the work over mass:

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.