#topic 9

thursday 12/05/22

i took these in class where we were doing thin film interference, it was super fun!! probably tbe best class in a while

January 2018, Bethlehem, West Bank

The sky was grey and the air cold and damp, matching the heaviness of my heart as I walked along Palestinian side of the infamous wall separating Israel from the West Bank. I was and remain a Zionist, firmly believing that the Jewish people have a right to a nation in their traditional homeland, and to safely dwell in their nation. Yet my heart broke as I took in story after story of hopelessness, depicted in art on the wall. The most confronting were the ones drawn by children.

The wall, together with Israeli checkpoints restrict freedom of movement for Palestinians between Bethlehem and Jerusalem and other parts of the West Bank. Travel through the checkpoints is regulated via a permit system. As such, access by Palestinians living on the ‘wrong’ side of the wall to education, healthcare, family, business, livelihood and farm lands is restricted. The ICJ advised that both the ICCPR and ICESCR continue to have effect in times of war and conflict (except when Art 4 of the ICCPR is called into effect in times of national emergency). Further, the Court observed that there are instances where a State may exercise jurisdiction extra-territorially, and where it does so they are bound to comply with the Conventions. Thus in areas subject to Israeli authority, Israel is bound to observe human rights, and where competence has passed to the Palestinian Authority, Israel must not ‘raise any obstacle to the exercise of such rights’.

The construction of the wall has had a significant effect on the people of the West Bank and their enjoyment of rights. The city of Qalqilya was enclosed by the wall, with only a single exit/entry point controlled by the military. Movement has been impeded, contrary to art 12 of the ICCPR. The wall has separated Palestinians from significant portions of their fertile farmland and water sources, thus affecting their means of making a living and access to food and water (ICESCR art 11). Access to health services and education institutions has been restricted (ICESCR arts 12 – 13, CROC arts 24, 28). Due to the now impeded route between Jerusalem and towns such as Bethlehem, businesses have been forced to shut down, and access to work made harder (triggering art 6 of ICESCR). People are separated from their family members who live on the other side of the wall (ICESCR art 10, CROC art 16).

It is, as the creator of the artwork observes, a prison.

admittedly i ran out of time on this particular task oops

🌸Pictorial history of your plant.

There are two ways you can think about this conceptually:

1. Suppose you have a generic wave described by the equation y = sin(kx + wt). After a given time from the start of its journey, t has increased. The golden rule is that the entire term inside the sin or cos function remains constant. So when t has increased, the value of (kx + wt) has increased. To compensate, x will decrease by an amount to compensate for the increase in t. And, of course, a decrease in x means that its displacement is in the negative direction.

The converse is true. So when you  have y = sin(kx - wt), after a certain time t has increased, and so the value of (kx - wt) has decreased. To compensate, x will increase, hence the motion in the positive direction.

The next most likely question is “Why does the term inside the sinusoidal function have to remain constant?” If you’re thinking about part of a part of the wave moving, then after a certain time t, you want to find that same part of the wave again to see where its moved to, which is why you’re looking for the same y-value. And if you’re looking for the same y-value, then you’re looking to keep the term inside the function constant.

2. What helps me remember it better is thinking about transformations of graphs, mathematically. If you had f(x) and f(x + k), the latter is the former shifted to the left, or the negative x-direction. This is because when a constant is added inside the function, the term is increased, and so the corresponding y-value occurs ‘sooner’ for a given x value, hence moving to the left. I’m not sure to what extent this is technically applicable to this situation in physics, but it fits, and if it helps remember the direction of propagation then why not?