If the rest energies of a proton and neutron (the two constituents of nuclei) are 938.3 and 939.6 MeV respectively, what is the difference in their masses in kilograms

Currents in dc transmission lines can be 100 a or higher. some people are concerned that the electromagnetic fields from such lines near their homes could pose health dangers. for a line that has current 150 a and a height of 8.0 m above the ground, what magnetic field does the line produce at ground level? express your answer in teslas and as a percentage of the earth’s magnetic field, which is 0.50 g. is this value cause for worry?