Please Answer both questions completely and show all answers. Question 2: A rock
ID: 2038844 • Letter: P
Question
Please Answer both questions completely and show all answers.
Question 2: A rock is thrown straight up from the surface of the Earth. Which one of the following statements describes the energy transformation of the rock as it rises? Neglect air resistance. [1 point] a) The total energy of the rock increases. b) The kinetic energy increases and the potential energy decreases. c) Both the potential energy and the total energy of the rock increase. d) The kinetic energy decreases and the potential energy increases e) Both the kinetic energy and the potential energy of the rock remain the same. Question 3: As a particle moves along the x axis it is acted by a conservative force. There are no non- conservative forces present. The potential energy is shown below as a function of the coordinate x of the particle. [3 points] a) Rank the labeled regions (AB, BC, CD) according to the magnitude of the force, least to greatest. U(x) B C D* Ranking: b) If the particle is released from point A with zero velocity, will it be able to reach point D? Explain your reasoningExplanation / Answer
Q-2
d)
as the rock thrown straight Up , the rock slows down due to acceleration due to gravity acting in down direction. since the speed decreases , the kinetic energy of the rock decreases.
as the rock thrown up , the height of the rock above the surface of earth increases and hence the potential energy of the rock increases.
3)
a)
we know that F = - dU/dx
CD>AB > BC
in region AB , the slope is negative and smaller than CD , hence the magnitude of force in AB is smaller than CD
in region BC , the slope is 0 , hence the magnitude of force is zero.
b)
No
the total energy has to remain same all the time
at A , there is no kinetic energy , hence the total energy is same as the potential energy at A
At D , the potential energy is greater than that at A, hence the total energy at D is greater. which is not right