Which force does the shuttle overcome to create an unbalanced net force as it initially lifts from the ground?

Sort the images based on whether there's a force of attraction or repulsion between the magnets shown. attraction repulsion

How does the entropy of steam compare to the entropy of ice?

Materials will have different energies associated with the electrons inside them. this is related to how strongly bound they are by their work function. if we sandwich a material with a very low energy between two materials with a high energy, we create a trap for an electron. if this trap is very narrow in one direction in comparison to the others, this is approximately a 1-dimensional box that confines the electron. what is the lowest energy of an electron in the box if the thinnest direction across the materials is 4.81 nm?