Aparallel-plate capacitor is formed from two 7.2 cm-diameter electrodes spaced 1.8 mm apart. the electric field strength inside the capacitor is 3.0×106n/c. what is the magnitude of the charge (in nc) on each electrode?

432 nC

Explanation: In order to calculate the charge,  we know that the electric field corresponding for two parallel-plate is given by:

E=Q/(area*e0)

In our case E=3.0x10^6 N/C

Area = Pix (0,072 m)^2

e0 vacuum permittivity 8,85x 10^-12

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.

i believe the answer would be:

d. violin, clarinet, french horn, and tuba