The graph in diagram shows the displacement-time graph of a roller skater. Calculate
a) The maximum velocity of the skater
b) The velocity of the skater when he returns to his
original position
c) The displacement of the skater when t= 50 s
d)The average velocity throughout the whole
journey
e) Average speed throughout the whole journey

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?