14 Two identical positively charged pith balls are brought up to touch one another, and then moved apart to their original distance Initially the first pith ball A carried twice
as much charge as the second pith bali B When they have separated both pith balls
each carry a charge of +6 nC. What was the original charge on the pith balls?
Pith ball A
Pith ball B
A
12
0
B
8
4
6
6
3
3
A positively charged plastic rod is placed above a thick metal plate The metal plate is
connected to the earth by a wire The metal plate rests on an insulator
posiilve ro]
metal plate
annihing wire
insulalor
​

Asap 1. which surface feature of the moon is characterized by mountainous areas? question options: maria terrae regolith craters 2.which statement describes surface features called maria on the moon? question options: layers of dust and rock deep areas of cooled lava deep, rocky and barren valleys highlands and mountainous areas

What is the role of the ocular lens?

The particle in a two-dimensional well is a useful model for the motion of electrons around the indole ring (3), the conjugated cycle found in the side chain of tryptophan. we may regard indole as a rectangle with sides of length 280 pm and 450 pm, with 10 electrons in the conjugated p system. as in case study 9.1, we assume that in the ground state of the molecule each quantized level is occupied by two electrons. (a) calculate the energy of an electron in the highest occupied level. (b) calculate the frequency of radiation that can induce a transition between the highest occupied and lowest unoccupied levels. 9.27 electrons around the porphine ring (4), the conjugated macrocycle that forms the structural basis of the heme group and the chlorophylls. we may treat the group as a circular ring of radius 440 pm, with 20 electrons in the conjugated system moving along the perimeter of the ring. as in exercise 9.26, assume that in the ground state of the molecule quantized each level is occupied by two electrons. (a) calculate the energy and angular momentum of an electron in the highest occupied level. (b) calculate the frequency of radiation that can induce a transition between the highest occupied and lowest unoccupied levels.