9.2 An AC generator is operating at a maximum emf of 340 V. It is connected
across a toaster and a kettle, as shown in the diagram below.
generator
800 W
2 000 W
The toaster is rated at 800 W, whlle the kettle is rated at 2 000 W. Both are
working under optimal conditions.
Calculate the:
9.2.1
mms current passing through the toaster
(3)
9.2.2
Total mms current delivered by the generator
(4)
1113

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?